proposal-iterator-methods.html

<!DOCTYPE html>
<html xmlns="http:/www.w3.org/1999/xhtml">
<head>
    <meta charset="utf-8" />
    <title>Iterator</title>
    <script src="proposal-iterator-methods.js" type="application/javascript;version=1.7"></script>
</head>
<body>
    <script>
(function () {'use strict';

var obj = {'0': '0', a:3, b: 'b'},
    is = '', isr = '', isrt = '';

document.write(
    Iterator(obj).some(function (key, val, i) {
        is += i;
        return key === val;
    }) + '<br >' + is + '<br >'
);

document.write(
    Iterator(obj, true).some(function (key, i) {
        isrt += i;
        return parseInt(key, 10) === i;
    }) + '<br >' + isrt + '<br >'
);



document.write(
    RegExp.iterator(/^(.*?): (.*)$/gm, 'key1: val1\nkey2: key2').some(function (n0, key, val, i) {
        isr += i;
        return key === val;
    }) + '<br >' + isr + '<br >'
);



}());
    </script>
</body>
</html>

proposal-iterator-methods.js

/*globals Iterator, StopIteration*/
(function () {'use strict';

// Todo: Should eventually match new iterator pattern; see http://www.2ality.com/2013/06/iterators-generators.html
// Todo: Add other relevant Array or Array-extra methods

Iterator.prototype.some = function (cb, thisObj) {
    thisObj = thisObj || null;
    var res, next;
    if (!this._i) {
        this._i = 0;
    }
    try {
        next = this.next();
    } catch(e) {
        if (e instanceof StopIteration) {
            return false;
        }
        throw e;
    }
    next = Array.isArray(next) ? next : [next];
    res = cb.apply(thisObj, next.concat(this._i));
    this._i++;
    if (res) {
        return true;
    }
    return this.some(cb, thisObj);
};

function _mixinRegex (regex, newFlags, newLastIndex) {
    newLastIndex = newLastIndex === undefined ? regex.lastIndex : newLastIndex;
    newFlags = newFlags || '';
    regex = new RegExp(
        regex.source,
        (newFlags.indexOf('g') > -1 ? 'g' : regex.global ? 'g' : '') +
            (newFlags.indexOf('i') > -1 ? 'i' : regex.ignoreCase ? 'i' : '') +
            (newFlags.indexOf('m') > -1 ? 'm' : regex.multiline ? 'm' : '') +
            (newFlags.indexOf('y') > -1 ? 'y' : regex.sticky ? 'y' : '') // Non-standard but harmless if already being used
    );
    regex.lastIndex = newLastIndex;
    return regex;
}

function RegExpIterator (pattern, string) {
    this.pattern = _mixinRegex(pattern, 'g');
    this.string = string;
}

RegExpIterator.prototype.some = Iterator.prototype.some;

RegExpIterator.prototype.next = function () {
    var matches = this.pattern.exec(this.string);
    if (matches !== null) {
        return matches;
    }
    throw StopIteration;
};
RegExpIterator.prototype['__iterator__'] = function (keysOnly) {
    return this;
};

RegExp.iterator = function (pattern, string) {
    return new RegExpIterator(pattern, string);
};

}());