Array Methods

aliases.js

(function () {
    Array.prototype.select = Array.prototype.map;
    Array.prototype.where = Array.prototype.filter;
    Array.prototype.all = Array.prototype.every;
    Array.prototype.any = Array.prototype.some;
    Array.prototype.agregate = Array.prototype.reduce;
    Array.prototype.fold = Array.prototype.reduce;
} ());

methods.js

(function () {
    //================================
    //==Ensure Array functions exist==
    //================================
    //(Required to support IE<9)

    if (!Array.prototype.filter) {
        Array.prototype.filter = function (fun /*, thisp */) {
            "use strict";

            if (this == null)
                throw new TypeError();

            var t = Object(this);
            var len = t.length >>> 0;
            if (typeof fun != "function")
                throw new TypeError();

            var res = [];
            var thisp = arguments[1];
            for (var i = 0; i < len; i++) {
                if (i in t) {
                    var val = t[i]; // in case fun mutates this
                    if (fun.call(thisp, val, i, t))
                        res.push(val);
                }
            }

            return res;
        };
    }
    if (!Array.prototype.forEach) {
        Array.prototype.forEach = function (callback, thisArg) {

            var T, k;

            if (this == null) {
                throw new TypeError(" this is null or not defined");
            }

            // 1. Let O be the result of calling ToObject passing the |this| value as the argument.
            var O = Object(this);

            // 2. Let lenValue be the result of calling the Get internal method of O with the argument "length".
            // 3. Let len be ToUint32(lenValue).
            var len = O.length >>> 0; // Hack to convert O.length to a UInt32

            // 4. If IsCallable(callback) is false, throw a TypeError exception.
            // See: http://es5.github.com/#x9.11
            if ({}.toString.call(callback) != "[object Function]") {
                throw new TypeError(callback + " is not a function");
            }

            // 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
            if (thisArg) {
                T = thisArg;
            }

            // 6. Let k be 0
            k = 0;

            // 7. Repeat, while k < len
            while (k < len) {

                var kValue;

                // a. Let Pk be ToString(k).
                // This is implicit for LHS operands of the in operator
                // b. Let kPresent be the result of calling the HasProperty internal method of O with argument Pk.
                // This step can be combined with c
                // c. If kPresent is true, then
                if (k in O) {

                    // i. Let kValue be the result of calling the Get internal method of O with argument Pk.
                    kValue = O[k];

                    // ii. Call the Call internal method of callback with T as the this value and
                    // argument list containing kValue, k, and O.
                    callback.call(T, kValue, k, O);
                }
                // d. Increase k by 1.
                k++;
            }
            // 8. return undefined
        };
    }
    if (!Array.prototype.every) {
        Array.prototype.every = function (fun /*, thisp */) {
            "use strict";

            if (this == null)
                throw new TypeError();

            var t = Object(this);
            var len = t.length >>> 0;
            if (typeof fun != "function")
                throw new TypeError();

            var thisp = arguments[1];
            for (var i = 0; i < len; i++) {
                if (i in t && !fun.call(thisp, t[i], i, t))
                    return false;
            }

            return true;
        };
    }
    if (!Array.prototype.map) {
        Array.prototype.map = function (callback, thisArg) {

            var T, A, k;

            if (this == null) {
                throw new TypeError(" this is null or not defined");
            }

            // 1. Let O be the result of calling ToObject passing the |this| value as the argument.
            var O = Object(this);

            // 2. Let lenValue be the result of calling the Get internal method of O with the argument "length".
            // 3. Let len be ToUint32(lenValue).
            var len = O.length >>> 0;

            // 4. If IsCallable(callback) is false, throw a TypeError exception.
            // See: http://es5.github.com/#x9.11
            if ({}.toString.call(callback) != "[object Function]") {
                throw new TypeError(callback + " is not a function");
            }

            // 5. If thisArg was supplied, let T be thisArg; else let T be undefined.
            if (thisArg) {
                T = thisArg;
            }

            // 6. Let A be a new array created as if by the expression new Array(len) where Array is
            // the standard built-in constructor with that name and len is the value of len.
            A = new Array(len);

            // 7. Let k be 0
            k = 0;

            // 8. Repeat, while k < len
            while (k < len) {

                var kValue, mappedValue;

                // a. Let Pk be ToString(k).
                // This is implicit for LHS operands of the in operator
                // b. Let kPresent be the result of calling the HasProperty internal method of O with argument Pk.
                // This step can be combined with c
                // c. If kPresent is true, then
                if (k in O) {

                    // i. Let kValue be the result of calling the Get internal method of O with argument Pk.
                    kValue = O[k];

                    // ii. Let mappedValue be the result of calling the Call internal method of callback
                    // with T as the this value and argument list containing kValue, k, and O.
                    mappedValue = callback.call(T, kValue, k, O);

                    // iii. Call the DefineOwnProperty internal method of A with arguments
                    // Pk, Property Descriptor {Value: mappedValue, Writable: true, Enumerable: true, Configurable: true},
                    // and false.

                    // In browsers that support Object.defineProperty, use the following:
                    // Object.defineProperty(A, Pk, { value: mappedValue, writable: true, enumerable: true, configurable: true });

                    // For best browser support, use the following:
                    A[k] = mappedValue;
                }
                // d. Increase k by 1.
                k++;
            }

            // 9. return A
            return A;
        };
    }
    if (!Array.prototype.some) {
        Array.prototype.some = function (fun /*, thisp */) {
            "use strict";

            if (this == null)
                throw new TypeError();

            var t = Object(this);
            var len = t.length >>> 0;
            if (typeof fun != "function")
                throw new TypeError();

            var thisp = arguments[1];
            for (var i = 0; i < len; i++) {
                if (i in t && fun.call(thisp, t[i], i, t))
                    return true;
            }

            return false;
        };
    }
    if (!Array.prototype.reduce) {
        Array.prototype.reduce = function reduce(accumulator) {
            var i, l = this.length, curr;

            if (typeof accumulator !== "function") // ES5 : "If IsCallable(callbackfn) is false, throw a TypeError exception."
                throw new TypeError("First argument is not callable");

            if ((l == 0 || l === null) && (arguments.length <= 1))// == on purpose to test 0 and false.
                throw new TypeError("Array length is 0 and no second argument");

            if (arguments.length <= 1) {
                curr = this[0]; // Increase i to start searching the secondly defined element in the array
                i = 1; // start accumulating at the second element
            }
            else {
                curr = arguments[1];
            }

            for (i = i || 0; i < l; ++i) {
                if (i in this)
                    curr = accumulator.call(undefined, curr, this[i], i, this);
            }

            return curr;
        };
    }
    if (!Array.prototype.reduceRight) {
        Array.prototype.reduceRight = function (callbackfn /*, initialValue */) {
            "use strict";

            if (this == null)
                throw new TypeError();

            var t = Object(this);
            var len = t.length >>> 0;
            if (typeof callbackfn != "function")
                throw new TypeError();

            // no value to return if no initial value, empty array
            if (len === 0 && arguments.length === 1)
                throw new TypeError();

            var k = len - 1;
            var accumulator;
            if (arguments.length >= 2) {
                accumulator = arguments[1];
            }
            else {
                do {
                    if (k in this) {
                        accumulator = this[k--];
                        break;
                    }

                    // if array contains no values, no initial value to return
                    if (--k < 0)
                        throw new TypeError();
                }
                while (true);
            }

            while (k >= 0) {
                if (k in t)
                    accumulator = callbackfn.call(undefined, accumulator, t[k], k, t);
                k--;
            }

            return accumulator;
        };
    }

    if (!Array.prototype.indexOf) {
        Array.prototype.indexOf = function (searchElement /*, fromIndex */) {
            "use strict";
            if (this == null) {
                throw new TypeError();
            }
            var t = Object(this);
            var len = t.length >>> 0;
            if (len === 0) {
                return -1;
            }
            var n = 0;
            if (arguments.length > 0) {
                n = Number(arguments[1]);
                if (n != n) { // shortcut for verifying if it's NaN
                    n = 0;
                } else if (n != 0 && n != Infinity && n != -Infinity) {
                    n = (n > 0 || -1) * Math.floor(Math.abs(n));
                }
            }
            if (n >= len) {
                return -1;
            }
            var k = n >= 0 ? n : Math.max(len - Math.abs(n), 0);
            for (; k < len; k++) {
                if (k in t && t[k] === searchElement) {
                    return k;
                }
            }
            return -1;
        }
    }
    if (!Array.prototype.lastIndexOf) {
        Array.prototype.lastIndexOf = function (searchElement /*, fromIndex*/) {
            "use strict";

            if (this == null)
                throw new TypeError();

            var t = Object(this);
            var len = t.length >>> 0;
            if (len === 0)
                return -1;

            var n = len;
            if (arguments.length > 1) {
                n = Number(arguments[1]);
                if (n != n)
                    n = 0;
                else if (n != 0 && n != (1 / 0) && n != -(1 / 0))
                    n = (n > 0 || -1) * Math.floor(Math.abs(n));
            }

            var k = (n >= 0) ? Math.min(n, len - 1) : len - Math.abs(n);

            for (; k >= 0; k--) {
                if (k in t && t[k] === searchElement)
                    return k;
            }
            return -1;
        };
    }
} ());