diff --git a/src/main/kotlin/RegexBuilder.kt b/src/main/kotlin/RegexBuilder.kt
index 36c7848..e6b9f1e 100644
--- a/src/main/kotlin/RegexBuilder.kt
+++ b/src/main/kotlin/RegexBuilder.kt
@@ -180,52 +180,52 @@ class RegexBuilder {
     fun nonDigit(quantifier: RegexQuantifier? = null) = append("\\D", quantifier)
 
     /**
-     * Add an element to match any letter in the Roman alphabet (a-z, A-Z)
+     * Add an element to match any Unicode letter.
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun letter(quantifier: RegexQuantifier? = null) = append("[a-zA-Z]", quantifier)
+    fun letter(quantifier: RegexQuantifier? = null) = append("\\p{L}", quantifier)
 
     /**
-     * Add an element to match any character that is not a letter in the Roman alphabet (a-z, A-Z)
+     * Add an element to match any character that is not a Unicode letter.
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun nonLetter(quantifier: RegexQuantifier? = null) = append("[^a-zA-Z]", quantifier)
+    fun nonLetter(quantifier: RegexQuantifier? = null) = append("\\P{L}", quantifier)
 
     /**
-     * Add an element to match any upper-case letter in the Roman alphabet (A-Z).
+     * Add an element to match any upper-case Unicode letter.
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun uppercaseLetter(quantifier: RegexQuantifier? = null) = append("[A-Z]", quantifier)
+    fun uppercaseLetter(quantifier: RegexQuantifier? = null) = append("\\p{Lu}", quantifier)
 
     /**
-     * Add an element to match any lowercase letter in the Roman alphabet (a-z)
+     * Add an element to match any lowercase Unicode letter.
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun lowercaseLetter(quantifier: RegexQuantifier? = null) = append("[a-z]", quantifier)
+    fun lowercaseLetter(quantifier: RegexQuantifier? = null) = append("\\p{Ll}", quantifier)
 
     /**
-     * Add an element to match any letter in the Roman alphabet or decimal digit (a-z, A-Z, 0-9)
+     * Add an element to match any Unicode letter or decimal digit.
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun letterOrDigit(quantifier: RegexQuantifier? = null) = append("[a-zA-Z0-9]", quantifier)
+    fun letterOrDigit(quantifier: RegexQuantifier? = null) = append("[\\p{L}0-9]", quantifier)
 
     /**
-     * Add an element to match any character that is not letter in the Roman alphabet or a decimal digit (a-z, A-Z, 0-9)
+     * Add an element to match any character that is not a Unicode letter or a decimal digit.
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun nonLetterOrDigit(quantifier: RegexQuantifier? = null) = append("[^a-zA-Z0-9]", quantifier)
+    fun nonLetterOrDigit(quantifier: RegexQuantifier? = null) = append("[^\\p{L}0-9]", quantifier)
 
     /**
      * Add an element to match any hexadecimal digit (a-f, A-F, 0-9)
@@ -260,21 +260,20 @@ class RegexBuilder {
     fun nonHexDigit(quantifier: RegexQuantifier? = null) = append("[^0-9A-Fa-f]", quantifier)
 
     /**
-     * Add an element to match any Roman alphabet letter, decimal digit, or underscore (a-z, A-Z, 0-9, _)
+     * Add an element to match any Unicode letter, decimal digit or underscore
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun wordCharacter(quantifier: RegexQuantifier? = null) = append("\\w", quantifier)
+    fun wordCharacter(quantifier: RegexQuantifier? = null) = append("[\\p{L}0-9_]", quantifier)
 
     /**
-     * Add an element to match any character that is not a Roman alphabet letter, decimal digit, or underscore
-     * (a-z, A-Z, 0-9, _)
+     * Add an element to match any character that is not a Unicode letter, decimal digit or underscore
      *
      * @param quantifier Quantifier to apply to this element
      * @return The current [RegexBuilder] object, for method chaining
      */
-    fun nonWordCharacter(quantifier: RegexQuantifier? = null) = append("\\W", quantifier)
+    fun nonWordCharacter(quantifier: RegexQuantifier? = null) = append("[^\\p{L}0-9_]", quantifier)
 
     /**
      * Add an element (a character class) to match any of the characters provided.
diff --git a/src/test/kotlin/RegexBuilderDslTest.kt b/src/test/kotlin/RegexBuilderDslTest.kt
index d9b9108..40e387e 100644
--- a/src/test/kotlin/RegexBuilderDslTest.kt
+++ b/src/test/kotlin/RegexBuilderDslTest.kt
@@ -41,9 +41,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.matches("Cat"))
         assertFalse(regex.matches("dog"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -75,9 +78,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("Cat"))
         assertFalse(regex.containsMatchIn("dog"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -107,9 +113,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.matches("Cat"))
         assertFalse(regex.containsMatchIn("dog"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -136,9 +145,12 @@ class RegexBuilderDslTest {
         assertEquals("\\\\\\.\\+\\*\\?\\[\\]\\{\\}\\(\\)\\|\\^\\$", regex.toString())
         assertTrue(regex.containsMatchIn("\\.+*?[]{}()|^$"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -171,9 +183,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("cat"))
         assertFalse(regex.containsMatchIn(" catheter"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -205,9 +220,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(""))
         assertFalse(regex.containsMatchIn("\n"))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -241,9 +259,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -280,9 +301,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("\n"))
         assertFalse(regex.containsMatchIn("\t\t\r\n   "))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -317,9 +341,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("abc"))
         assertTrue(regex.containsMatchIn("xFFF"))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -353,9 +380,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -389,9 +419,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -425,9 +458,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -461,9 +497,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -496,9 +535,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("abc"))
         assertFalse(regex.containsMatchIn("xFFF"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -532,9 +574,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("0"))
         assertFalse(regex.containsMatchIn("999"))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -558,7 +603,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("a"))
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        z"))
@@ -568,9 +613,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("%"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -594,7 +642,7 @@ class RegexBuilderDslTest {
             nonLetter()
         }
 
-        assertEquals("[^a-zA-Z]", regex.toString())
+        assertEquals("\\P{L}", regex.toString())
         assertTrue(regex.containsMatchIn(" 1"))
         assertTrue(regex.containsMatchIn("0"))
         assertTrue(regex.containsMatchIn("999_"))
@@ -604,9 +652,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("ZZZ"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -630,7 +681,7 @@ class RegexBuilderDslTest {
             uppercaseLetter()
         }
 
-        assertEquals("[A-Z]", regex.toString())
+        assertEquals("\\p{Lu}", regex.toString())
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -640,9 +691,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -666,7 +720,7 @@ class RegexBuilderDslTest {
             lowercaseLetter()
         }
 
-        assertEquals("[a-z]", regex.toString())
+        assertEquals("\\p{Ll}", regex.toString())
         assertTrue(regex.containsMatchIn("a"))
         assertTrue(regex.containsMatchIn("        z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -676,9 +730,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("S"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -702,7 +759,7 @@ class RegexBuilderDslTest {
             letterOrDigit()
         }
 
-        assertEquals("[a-zA-Z0-9]", regex.toString())
+        assertEquals("[\\p{L}0-9]", regex.toString())
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -713,9 +770,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -739,7 +799,7 @@ class RegexBuilderDslTest {
             nonLetterOrDigit()
         }
 
-        assertEquals("[^a-zA-Z0-9]", regex.toString())
+        assertEquals("[^\\p{L}0-9]", regex.toString())
         assertFalse(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -750,9 +810,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -787,9 +850,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -824,9 +890,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -861,9 +930,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -898,9 +970,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -924,7 +999,7 @@ class RegexBuilderDslTest {
             wordCharacter()
         }
 
-        assertEquals("\\w", regex.toString())
+        assertEquals("[\\p{L}0-9_]", regex.toString())
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -935,9 +1010,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -961,7 +1039,7 @@ class RegexBuilderDslTest {
             nonWordCharacter()
         }
 
-        assertEquals("\\W", regex.toString())
+        assertEquals("[^\\p{L}0-9_]", regex.toString())
         assertFalse(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -972,9 +1050,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1008,9 +1089,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1044,9 +1128,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1080,9 +1167,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1117,9 +1207,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1149,9 +1242,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("dog"))
         assertTrue(regex.containsMatchIn("|"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1188,9 +1284,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("||"))
         assertTrue(regex.containsMatchIn("|||"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1220,9 +1319,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("dog"))
         assertTrue(regex.containsMatchIn("|"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1259,9 +1361,12 @@ class RegexBuilderDslTest {
         assertTrue(regex.containsMatchIn("||"))
         assertTrue(regex.containsMatchIn("|||"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1311,9 +1416,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1349,9 +1457,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1389,9 +1500,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1419,7 +1533,7 @@ class RegexBuilderDslTest {
             }
         }
 
-        assertEquals(".*([a-zA-Z]\\d)", regex.toString())
+        assertEquals(".*(\\p{L}\\d)", regex.toString())
 
         var match = regex.find("Class A1")
         assertNotNull(match)
@@ -1439,9 +1553,12 @@ class RegexBuilderDslTest {
         match = regex.find("A 4-legged dog")
         assertNull(match)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1468,7 +1585,7 @@ class RegexBuilderDslTest {
             }
         }
 
-        assertEquals("([a-zA-Z]\\d)", regex.toString())
+        assertEquals("(\\p{L}\\d)", regex.toString())
 
         var matcher = regex.find("Class A1 f2 ZZ88")
         val matches = mutableListOf<String>()
@@ -1481,9 +1598,12 @@ class RegexBuilderDslTest {
         assertEquals("f2", matches[1])
         assertEquals("Z8", matches[2])
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1511,7 +1631,7 @@ class RegexBuilderDslTest {
             lowercaseLetter(OneOrMore)
         }
 
-        assertEquals("[a-z]+(?<test123>\\d+)[a-z]+", regex.toString())
+        assertEquals("\\p{Ll}+(?<test123>\\d+)\\p{Ll}+", regex.toString())
 
         val match = regex.find("a99z")
         assertNotNull(match)
@@ -1519,9 +1639,12 @@ class RegexBuilderDslTest {
         assertEquals("99", match.groupValues[1])
         assertEquals("99", match.groups["test123"]?.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1549,16 +1672,19 @@ class RegexBuilderDslTest {
             lowercaseLetter(OneOrMore)
         }
 
-        assertEquals("[a-z]+(?:\\d+)[a-z]+", regex.toString())
+        assertEquals("\\p{Ll}+(?:\\d+)\\p{Ll}+", regex.toString())
 
         val match = regex.find("a99z")
         assertNotNull(match)
         assertEquals("a99z", match!!.value)
         assertEquals(1, match.groups.size)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1588,7 +1714,7 @@ class RegexBuilderDslTest {
             }
         }
 
-        assertEquals("(.*)([a-zA-Z]\\d)", regex.toString())
+        assertEquals("(.*)(\\p{L}\\d)", regex.toString())
 
         var match = regex.find("Class A1")
         assertNotNull(match)
@@ -1611,9 +1737,12 @@ class RegexBuilderDslTest {
         match = regex.find("A 4-legged dog")
         assertNull(match)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1644,7 +1773,7 @@ class RegexBuilderDslTest {
             }
         }
 
-        assertEquals(".(.*([a-zA-Z]\\d))", regex.toString())
+        assertEquals(".(.*(\\p{L}\\d))", regex.toString())
 
         var match = regex.find("Class A1")
         assertNotNull(match)
@@ -1667,9 +1796,12 @@ class RegexBuilderDslTest {
         match = regex.find("A 4-legged dog")
         assertNull(match)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1695,7 +1827,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]\\d*[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d*\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a123b"))
@@ -1704,9 +1836,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1732,7 +1867,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]\\d+[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d+\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a123b"))
@@ -1741,9 +1876,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1769,7 +1907,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]\\d?[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d?\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertFalse(regex.containsMatchIn("a123b"))
@@ -1778,9 +1916,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1806,7 +1947,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]\\d{3}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{3}\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertFalse(regex.containsMatchIn("a1b"))
         assertFalse(regex.containsMatchIn("a12b"))
@@ -1818,9 +1959,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1846,7 +1990,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]\\d{3,}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{3,}\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertFalse(regex.containsMatchIn("a1b"))
         assertFalse(regex.containsMatchIn("a12b"))
@@ -1858,9 +2002,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1886,7 +2033,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]\\d{0,3}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{0,3}\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a12b"))
@@ -1898,9 +2045,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1926,7 +2076,7 @@ class RegexBuilderDslTest {
             letter()
         }
 
-        assertEquals("[a-zA-Z]\\d{2,4}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{2,4}\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertFalse(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a12b"))
@@ -1938,9 +2088,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1976,9 +2129,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" find me! "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2012,9 +2168,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2056,9 +2215,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("a@b.c"))
         assertFalse(regex.containsMatchIn("  @  .  "))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2109,9 +2271,12 @@ class RegexBuilderDslTest {
         assertNotNull(match)
         assertEquals("http://www.mainwave.co.uk", match!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2155,9 +2320,12 @@ class RegexBuilderDslTest {
         assertFalse(regex.containsMatchIn("1.1.1.1.1"))
         assertFalse(regex.containsMatchIn("1.1.1.1000"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2186,9 +2354,12 @@ class RegexBuilderDslTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("", nonGreedyMatch!!.value)
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2217,9 +2388,12 @@ class RegexBuilderDslTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("9", nonGreedyMatch!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2248,9 +2422,12 @@ class RegexBuilderDslTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("9", nonGreedyMatch!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2279,9 +2456,12 @@ class RegexBuilderDslTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("99", nonGreedyMatch!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2310,9 +2490,12 @@ class RegexBuilderDslTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("", nonGreedyMatch!!.value)
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2341,9 +2524,12 @@ class RegexBuilderDslTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("", nonGreedyMatch!!.value)
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
diff --git a/src/test/kotlin/RegexBuilderTest.kt b/src/test/kotlin/RegexBuilderTest.kt
index 53c22a4..2e52f59 100644
--- a/src/test/kotlin/RegexBuilderTest.kt
+++ b/src/test/kotlin/RegexBuilderTest.kt
@@ -41,9 +41,12 @@ class RegexBuilderTest {
         assertFalse(regex.matches("Cat"))
         assertFalse(regex.matches("dog"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -75,9 +78,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("Cat"))
         assertFalse(regex.containsMatchIn("dog"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -107,9 +113,12 @@ class RegexBuilderTest {
         assertTrue(regex.matches("Cat"))
         assertFalse(regex.containsMatchIn("dog"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -136,9 +145,12 @@ class RegexBuilderTest {
         assertEquals("\\\\\\.\\+\\*\\?\\[\\]\\{\\}\\(\\)\\|\\^\\$", regex.toString())
         assertTrue(regex.containsMatchIn("\\.+*?[]{}()|^$"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -171,9 +183,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("cat"))
         assertFalse(regex.containsMatchIn(" catheter"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -205,9 +220,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(""))
         assertFalse(regex.containsMatchIn("\n"))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -241,9 +259,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -280,9 +301,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("\n"))
         assertFalse(regex.containsMatchIn("\t\t\r\n   "))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -317,9 +341,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("abc"))
         assertTrue(regex.containsMatchIn("xFFF"))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -353,9 +380,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -389,9 +419,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -425,9 +458,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -461,9 +497,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("                hi!"))
         assertFalse(regex.containsMatchIn("cat"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -496,9 +535,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("abc"))
         assertFalse(regex.containsMatchIn("xFFF"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -532,9 +574,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("0"))
         assertFalse(regex.containsMatchIn("999"))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -558,7 +603,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("a"))
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        z"))
@@ -568,9 +613,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("%"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -594,7 +642,7 @@ class RegexBuilderTest {
             .nonLetter()
             .buildRegex()
 
-        assertEquals("[^a-zA-Z]", regex.toString())
+        assertEquals("\\P{L}", regex.toString())
         assertTrue(regex.containsMatchIn(" 1"))
         assertTrue(regex.containsMatchIn("0"))
         assertTrue(regex.containsMatchIn("999_"))
@@ -604,9 +652,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("ZZZ"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -630,7 +681,7 @@ class RegexBuilderTest {
             .uppercaseLetter()
             .buildRegex()
 
-        assertEquals("[A-Z]", regex.toString())
+        assertEquals("\\p{Lu}", regex.toString())
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -640,9 +691,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -666,7 +720,7 @@ class RegexBuilderTest {
             .lowercaseLetter()
             .buildRegex()
 
-        assertEquals("[a-z]", regex.toString())
+        assertEquals("\\p{Ll}", regex.toString())
         assertTrue(regex.containsMatchIn("a"))
         assertTrue(regex.containsMatchIn("        z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -676,9 +730,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("S"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -702,7 +759,7 @@ class RegexBuilderTest {
             .letterOrDigit()
             .buildRegex()
 
-        assertEquals("[a-zA-Z0-9]", regex.toString())
+        assertEquals("[\\p{L}0-9]", regex.toString())
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -713,9 +770,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -739,7 +799,7 @@ class RegexBuilderTest {
             .nonLetterOrDigit()
             .buildRegex()
 
-        assertEquals("[^a-zA-Z0-9]", regex.toString())
+        assertEquals("[^\\p{L}0-9]", regex.toString())
         assertFalse(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -750,9 +810,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -787,9 +850,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -824,9 +890,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -861,9 +930,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -898,9 +970,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -924,7 +999,7 @@ class RegexBuilderTest {
             .wordCharacter()
             .buildRegex()
 
-        assertEquals("\\w", regex.toString())
+        assertEquals("[\\p{L}0-9_]", regex.toString())
         assertTrue(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -935,9 +1010,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -961,7 +1039,7 @@ class RegexBuilderTest {
             .nonWordCharacter()
             .buildRegex()
 
-        assertEquals("\\W", regex.toString())
+        assertEquals("[^\\p{L}0-9_]", regex.toString())
         assertFalse(regex.containsMatchIn("A"))
         assertTrue(regex.containsMatchIn("        Z"))
         assertTrue(regex.containsMatchIn("text with Spaces"))
@@ -972,9 +1050,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("s"))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1008,9 +1089,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1044,9 +1128,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1080,9 +1167,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1117,9 +1207,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1149,9 +1242,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("dog"))
         assertTrue(regex.containsMatchIn("|"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1188,9 +1284,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("||"))
         assertTrue(regex.containsMatchIn("|||"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1220,9 +1319,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("dog"))
         assertTrue(regex.containsMatchIn("|"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1259,9 +1361,12 @@ class RegexBuilderTest {
         assertTrue(regex.containsMatchIn("||"))
         assertTrue(regex.containsMatchIn("|||"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1311,9 +1416,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1349,9 +1457,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1389,9 +1500,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1419,7 +1533,7 @@ class RegexBuilderTest {
             .endGroup()
             .buildRegex()
 
-        assertEquals(".*([a-zA-Z]\\d)", regex.toString())
+        assertEquals(".*(\\p{L}\\d)", regex.toString())
 
         var match = regex.find("Class A1")
         assertNotNull(match)
@@ -1439,9 +1553,12 @@ class RegexBuilderTest {
         match = regex.find("A 4-legged dog")
         assertNull(match)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1468,7 +1585,7 @@ class RegexBuilderTest {
             .endGroup()
             .buildRegex()
 
-        assertEquals("([a-zA-Z]\\d)", regex.toString())
+        assertEquals("(\\p{L}\\d)", regex.toString())
 
         var matcher = regex.find("Class A1 f2 ZZ88")
         val matches = mutableListOf<String>()
@@ -1481,9 +1598,12 @@ class RegexBuilderTest {
         assertEquals("f2", matches[1])
         assertEquals("Z8", matches[2])
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1511,7 +1631,7 @@ class RegexBuilderTest {
             .lowercaseLetter(OneOrMore)
             .buildRegex()
 
-        assertEquals("[a-z]+(?<test123>\\d+)[a-z]+", regex.toString())
+        assertEquals("\\p{Ll}+(?<test123>\\d+)\\p{Ll}+", regex.toString())
 
         val match = regex.find("a99z")
         assertNotNull(match)
@@ -1519,9 +1639,12 @@ class RegexBuilderTest {
         assertEquals("99", match.groupValues[1])
         assertEquals("99", match.groups["test123"]?.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1549,16 +1672,19 @@ class RegexBuilderTest {
             .lowercaseLetter(OneOrMore)
             .buildRegex()
 
-        assertEquals("[a-z]+(?:\\d+)[a-z]+", regex.toString())
+        assertEquals("\\p{Ll}+(?:\\d+)\\p{Ll}+", regex.toString())
 
         val match = regex.find("a99z")
         assertNotNull(match)
         assertEquals("a99z", match!!.value)
         assertEquals(1, match.groups.size)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1588,7 +1714,7 @@ class RegexBuilderTest {
             .endGroup()
             .buildRegex()
 
-        assertEquals("(.*)([a-zA-Z]\\d)", regex.toString())
+        assertEquals("(.*)(\\p{L}\\d)", regex.toString())
 
         var match = regex.find("Class A1")
         assertNotNull(match)
@@ -1611,9 +1737,12 @@ class RegexBuilderTest {
         match = regex.find("A 4-legged dog")
         assertNull(match)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1644,7 +1773,7 @@ class RegexBuilderTest {
             .endGroup()
             .buildRegex()
 
-        assertEquals(".(.*([a-zA-Z]\\d))", regex.toString())
+        assertEquals(".(.*(\\p{L}\\d))", regex.toString())
 
         var match = regex.find("Class A1")
         assertNotNull(match)
@@ -1667,9 +1796,12 @@ class RegexBuilderTest {
         match = regex.find("A 4-legged dog")
         assertNull(match)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1695,7 +1827,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]\\d*[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d*\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a123b"))
@@ -1704,9 +1836,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1732,7 +1867,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]\\d+[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d+\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a123b"))
@@ -1741,9 +1876,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1769,7 +1907,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]\\d?[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d?\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertFalse(regex.containsMatchIn("a123b"))
@@ -1778,9 +1916,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1806,7 +1947,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]\\d{3}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{3}\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertFalse(regex.containsMatchIn("a1b"))
         assertFalse(regex.containsMatchIn("a12b"))
@@ -1818,9 +1959,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1846,7 +1990,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]\\d{3,}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{3,}\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertFalse(regex.containsMatchIn("a1b"))
         assertFalse(regex.containsMatchIn("a12b"))
@@ -1858,9 +2002,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1886,7 +2033,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]\\d{0,3}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{0,3}\\p{L}", regex.toString())
         assertTrue(regex.containsMatchIn("ab"))
         assertTrue(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a12b"))
@@ -1898,9 +2045,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1926,7 +2076,7 @@ class RegexBuilderTest {
             .letter()
             .buildRegex()
 
-        assertEquals("[a-zA-Z]\\d{2,4}[a-zA-Z]", regex.toString())
+        assertEquals("\\p{L}\\d{2,4}\\p{L}", regex.toString())
         assertFalse(regex.containsMatchIn("ab"))
         assertFalse(regex.containsMatchIn("a1b"))
         assertTrue(regex.containsMatchIn("a12b"))
@@ -1938,9 +2088,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -1976,9 +2129,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" find me! "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2012,9 +2168,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn(" "))
         assertFalse(regex.containsMatchIn(""))
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2056,9 +2215,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("a@b.c"))
         assertFalse(regex.containsMatchIn("  @  .  "))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2109,9 +2271,12 @@ class RegexBuilderTest {
         assertNotNull(match)
         assertEquals("http://www.mainwave.co.uk", match!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2155,9 +2320,12 @@ class RegexBuilderTest {
         assertFalse(regex.containsMatchIn("1.1.1.1.1"))
         assertFalse(regex.containsMatchIn("1.1.1.1000"))
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertFalse(regex.containsMatchIn(DECIMAL_DIGITS))
         assertFalse(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertFalse(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2209,9 +2377,12 @@ class RegexBuilderTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("", nonGreedyMatch!!.value)
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2240,9 +2411,12 @@ class RegexBuilderTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("9", nonGreedyMatch!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2271,9 +2445,12 @@ class RegexBuilderTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("9", nonGreedyMatch!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2302,9 +2479,12 @@ class RegexBuilderTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("99", nonGreedyMatch!!.value)
 
-        assertFalse(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertFalse(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertFalse(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertFalse(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2333,9 +2513,12 @@ class RegexBuilderTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("", nonGreedyMatch!!.value)
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
@@ -2364,9 +2547,12 @@ class RegexBuilderTest {
         assertNotNull(nonGreedyMatch)
         assertEquals("", nonGreedyMatch!!.value)
 
-        assertTrue(regex.containsMatchIn(BOTH_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(UPPER_CASE_ALPHABET))
-        assertTrue(regex.containsMatchIn(LOWER_CASE_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_LATIN_ALPHABET))
+        assertTrue(regex.containsMatchIn(BOTH_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(UPPER_CASE_EXTENDED_ALPHABET))
+        assertTrue(regex.containsMatchIn(LOWER_CASE_EXTENDED_ALPHABET))
         assertTrue(regex.containsMatchIn(DECIMAL_DIGITS))
         assertTrue(regex.containsMatchIn(BOTH_CASE_HEX_DIGITS))
         assertTrue(regex.containsMatchIn(UPPER_CASE_HEX_DIGITS))
diff --git a/src/test/kotlin/TestConsts.kt b/src/test/kotlin/TestConsts.kt
index 4469052..0a6921c 100644
--- a/src/test/kotlin/TestConsts.kt
+++ b/src/test/kotlin/TestConsts.kt
@@ -1,7 +1,10 @@
 // Character classes
-const val BOTH_CASE_ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
-const val UPPER_CASE_ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
-const val LOWER_CASE_ALPHABET = "abcdefghijklmnopqrstuvwxyz"
+const val BOTH_CASE_LATIN_ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz"
+const val UPPER_CASE_LATIN_ALPHABET = "ABCDEFGHIJKLMNOPQRSTUVWXYZ"
+const val LOWER_CASE_LATIN_ALPHABET = "abcdefghijklmnopqrstuvwxyz"
+const val BOTH_CASE_EXTENDED_ALPHABET = "ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞẞĀĂĄĆĈĊČĎĐĒĔĖĘĚĜĞĠĢĤĦĨĪĬĮİĴĶĹĻĽĿŁŃŅŇŊŌŎŐŒŔŖŘŚŜŞŠŢŤŦŨŪŬŮŰŲŴŶŸŹŻŽàáâãäåæçèéêëìíîïðñòóôõöøùúûüýþßāăąćĉċčďđēĕėęěĝğġģĥħĩīĭįiĵķĺļľŀłńņňŋōŏőœŕŗřśŝşšţťŧũūŭůűųŵŷÿźżž"
+const val UPPER_CASE_EXTENDED_ALPHABET = "ÀÁÂÃÄÅÆÇÈÉÊËÌÍÎÏÐÑÒÓÔÕÖØÙÚÛÜÝÞẞĀĂĄĆĈĊČĎĐĒĔĖĘĚĜĞĠĢĤĦĨĪĬĮİĴĶĹĻĽĿŁŃŅŇŊŌŎŐŒŔŖŘŚŜŞŠŢŤŦŨŪŬŮŰŲŴŶŸŹŻŽ"
+const val LOWER_CASE_EXTENDED_ALPHABET = "àáâãäåæçèéêëìíîïðñòóôõöøùúûüýþßāăąćĉċčďđēĕėęěĝğġģĥħĩīĭįiĵķĺļľŀłńņňŋōŏőœŕŗřśŝşšţťŧũūŭůűųŵŷÿźżž"
 const val DECIMAL_DIGITS = "0123456789"
 const val BOTH_CASE_HEX_DIGITS = "0123456789ABCDEFabcdef"
 const val UPPER_CASE_HEX_DIGITS = "0123456789ABCDEF"