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ArrayList Polyfill Shims for JS Arrays
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| // ArrayList Polyfill Shims for JS Arrays (v1.0.1) | |
| // GoToLoop (2020/Nov/05) | |
| // https://Gist.GitHub.com/GoToLoop/a74c5780667f2610097cfc007e53a559 | |
| "use strict"; | |
| // Add some useful Java list's methods to JS arrays as polyfills: | |
| Object.defineProperties(Array.prototype, { | |
| size: { | |
| value() { // polyfill hack to add method size() to JS arrays | |
| return this.length; // return array's current length | |
| } | |
| }, | |
| isEmpty: { | |
| value() { // polyfill hack to add method isEmpty() to JS arrays | |
| return !this.length; // return true if length is 0 | |
| } | |
| }, | |
| clear: { | |
| value() { // polyfill hack to add method clear() to JS arrays | |
| return this.length = 0, this; // remove all elements | |
| } | |
| }, | |
| get: { | |
| value(idx) { // polyfill hack to add method get() to JS arrays | |
| return this[idx]; // so its indices can be accessed like a Java list | |
| } | |
| }, | |
| set: { | |
| value(idx, elem) { // polyfill hack to add method set() to JS arrays | |
| return this[idx] = elem; // replace elem at specified index | |
| } | |
| }, | |
| add: { | |
| value() { // polyfill hack to add method add() to JS arrays | |
| arguments.length > 1? | |
| this.splice(arguments[0], 0, arguments[1]) : // add at specified index | |
| this.push(arguments[0]); // append to array's tail | |
| return this; | |
| } | |
| }, | |
| addAll: { | |
| value() { // polyfill hack to add method addAll() to JS arrays | |
| arguments.length > 1? | |
| this.splice(arguments[0], 0, ...arguments[1]) : // add all at index | |
| this.push(...arguments[0]); // append all items to array's tail | |
| return this; | |
| } | |
| }, | |
| remove: { | |
| value(val) { // polyfill hack to add method remove() to JS arrays | |
| // idx is val if its type is number, otherwise find its index: | |
| const idx = typeof val == 'number'? val : this.indexOf(val); | |
| // Remove & return the element at index idx or return false: | |
| return ~idx? this.splice(idx, 1)[0] : false; | |
| } | |
| }, | |
| toArray: { | |
| value() { // polyfill hack to add method toArray() to JS arrays | |
| if (!arguments.length) return this.slice(); // returns array clone | |
| const [ arr ] = arguments, arrLen = arr.length, thisLen = this.length; | |
| if (arrLen < thisLen) return this.slice(); // returns clone if too small | |
| else if (arrLen > thisLen) arr[thisLen] = null; // marks the array end | |
| for (var i = 0; i < thisLen; arr[i] = this[i++]); // array transfer | |
| return arr; // returns passed array filled w/ this array | |
| } | |
| }, | |
| clone: { // method clone() is like invoking slice() w/ no arguments | |
| value: Array.prototype.slice | |
| } | |
| }); |
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