feat: result ok and err methods

starkware-libs · May 15, 2024 · 026f8ef · 026f8ef
1 parent 000b834
commit 026f8ef
Show file tree

Hide file tree

Showing 2 changed files with 66 additions and 0 deletions.
diff --git a/corelib/src/result.cairo b/corelib/src/result.cairo
@@ -81,4 +81,46 @@ pub impl ResultTraitImpl<T, E> of ResultTrait<T, E> {
             Result::Err(_) => false,
         }
     }
+
+    /// Converts from `Result<T, E>` to `Option<T>`.
+    ///
+    /// Converts `self` into an `Option<T>`, consuming `self`,
+    /// and discarding the error, if any.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// let x: Result<u32, ByteArray> = Result::Ok(2);
+    /// assert_eq!(x.ok(), Option::Some(2));
+    ///
+    /// let x: Result<u32, ByteArray> = Result::Err("Nothing here");
+    /// assert!(x.ok().is_none());
+    /// ```
+    fn ok<+Drop<T>, +Drop<E>>(self: Result<T, E>) -> Option<T> {
+        match self {
+            Result::Ok(x) => Option::Some(x),
+            Result::Err(_) => Option::None,
+        }
+    }
+
+    /// Converts from `Result<T, E>` to `Option<E>`.
+    ///
+    /// Converts `self` into an `Option<E>`, consuming `self`,
+    /// and discarding the success value, if any.
+    ///
+    /// # Examples
+    ///
+    /// ```
+    /// let x: Result<u32, ByteArray> = Result::Err("Nothing here");
+    /// assert_eq!(x.err(), Option::Some("Nothing here"));
+    ///
+    /// let x: Result<u32, ByteArray> = Result::Ok(2);
+    /// assert!(x.err().is_none());
+    /// ```
+    fn err<+Drop<T>, +Drop<E>>(self: Result<T, E>) -> Option<E> {
+        match self {
+            Result::Ok(_) => Option::None,
+            Result::Err(x) => Option::Some(x),
+        }
+    }
 }
diff --git a/corelib/src/test/result_test.cairo b/corelib/src/test/result_test.cairo
@@ -123,3 +123,27 @@ fn test_result_err_into_is_ok() {
     let result: Result<u32, felt252> = Result::Err('no');
     assert(!result.into_is_ok(), 'result_err_into_is_ok');
 }
+
+#[test]
+fn test_result_ok_ok_should_return_ok_value() {
+    let x: Result<u32, ByteArray> = Result::Ok(2);
+    assert_eq!(x.ok(), Option::Some(2));
+}
+
+#[test]
+fn test_result_err_ok_should_return_none() {
+    let x: Result<u32, ByteArray> = Result::Err("Nothing here");
+    assert!(x.ok().is_none());
+}
+
+#[test]
+fn test_result_err_err_should_return_error_value() {
+    let x: Result<u32, ByteArray> = Result::Err("Nothing here");
+    assert_eq!(x.err(), Option::Some("Nothing here"));
+}
+
+#[test]
+fn test_result_ok_err_should_return_none() {
+    let x: Result<u32, ByteArray> = Result::Ok(2);
+    assert!(x.err().is_none());
+}