Add new Circular#filter(fn) class method

klaudiosinani · Apr 2, 2019 · 32f6aa2 · 32f6aa2
1 parent 67781ff
commit 32f6aa2
Showing 1 changed file with 61 additions and 49 deletions.
diff --git a/src/circular.js b/src/circular.js
@@ -65,6 +65,63 @@ class Circular extends List {
     return this;
   }
 
+  filter(fn) {
+    const list = new Circular();
+
+    this.forEach(x => {
+      if (fn(x)) {
+        list.append(x);
+      }
+    });
+
+    return list;
+  }
+
+  forEach(fn) {
+    let {_head: node} = this;
+
+    if (node) {
+      do {
+        fn(node.value);
+        node = node.next;
+      } while (node !== this._head);
+    }
+
+    return this;
+  }
+
+  insert({value, index = this.length}) {
+    this._arrayify(value).forEach(value => {
+      return (index <= 0) ? this._addHead(value) : this._addNode(value, index);
+    });
+    return this;
+  }
+
+  join(separator = ',') {
+    let result = '';
+    let {_head: node} = this;
+
+    if (node) {
+      do {
+        result += node.value;
+
+        if (node.next !== this._head) {
+          result += separator;
+        }
+
+        node = node.next;
+      } while (node !== this._head);
+    }
+
+    return result;
+  }
+
+  map(fn) {
+    const list = new Circular();
+    this.forEach(x => list.append(fn(x)));
+    return list;
+  }
+
   prepend(...values) {
     values.forEach(value => {
       if (this.isEmpty()) {
@@ -86,13 +143,6 @@ class Circular extends List {
     return result;
   }
 
-  insert({value, index = this.length}) {
-    this._arrayify(value).forEach(value => {
-      return (index <= 0) ? this._addHead(value) : this._addNode(value, index);
-    });
-    return this;
-  }
-
   remove(index = this.length - 1) {
     if (!this._isValid(index)) {
       return undefined;
@@ -105,17 +155,10 @@ class Circular extends List {
     return this._removeNode(index);
   }
 
-  forEach(fn) {
-    let {_head: node} = this;
-
-    if (node) {
-      do {
-        fn(node.value);
-        node = node.next;
-      } while (node !== this._head);
-    }
-
-    return this;
+  reverse() {
+    const list = new Circular();
+    this.forEach(x => list.prepend(x));
+    return list;
   }
 
   toArray() {
@@ -130,37 +173,6 @@ class Circular extends List {
     this.forEach(x => list.append(x));
     return list;
   }
-
-  map(fn) {
-    const list = new Circular();
-    this.forEach(x => list.append(fn(x)));
-    return list;
-  }
-
-  join(separator = ',') {
-    let result = '';
-    let {_head: node} = this;
-
-    if (node) {
-      do {
-        result += node.value;
-
-        if (node.next !== this._head) {
-          result += separator;
-        }
-
-        node = node.next;
-      } while (node !== this._head);
-    }
-
-    return result;
-  }
-
-  reverse() {
-    const list = new Circular();
-    this.forEach(x => list.prepend(x));
-    return list;
-  }
 }
 
 module.exports = Circular;