Nodejs Array Where where(predicate)

Method Source Code

/**//from w ww .  j ava2 s.  com
 * @author Tao Chen
 */
Array.prototype.where = function(predicate) {
    if (typeof(predicate) != "function") {
        throw new Error("The argument must be a function");
    }
    var arr = [];
    var index = 0;
    var len = this.length;
    for (var i = 0; i < len; i++) {
        if (predicate(this[i])) {
            arr[index++] = this[i];
        }
    }
    return arr;
};

Related

1. where(inclusionTest)

   Array.prototype.where = function (inclusionTest) {
       var results = [];
       for (var i = 0; i < this.length; i++) {
           if (inclusionTest(this[i]))
               results.push(this[i]);
       return results;
   };
   Array.prototype.select = function (projection) {
   ...
   

2. where(inclusionTest)

   Array.prototype.where = function (inclusionTest) {
       var results = [];
       for (var i = 0; i < this.length; i++) {
           if (inclusionTest(this[i]))
               results.push(this[i]);
       return results;
   };
   

3. where(predicate)

   Array.prototype.where = function(predicate) {
       var derivedArray = [];
       for (i = 0; i < this.length; i += 1) {
           if (predicate(this[i])) {
               derivedArray.push(this[i]);
       return derivedArray;
   

4. where(predicate)

   Array.prototype.where = function (predicate) {
       if (predicate == null || typeof (predicate) !== 'function') throw new Error('predicate should');
       var result = [];
       for (var i = 0; i < this.length; i++) {
           if (predicate(this[i], i)) result.push(this[i]);
       return result;
   };
   

5. where(predicate)

   Array.prototype.where = function (predicate) {
       var ret = [];
       for (var i = 0; i < this.length; ++i) {
           if (predicate(this[i], i))
               ret.push(this[i]);
       return ret;
   };
   

6. where(predicate, context)

   Array.prototype.where = Array.prototype.filter || function (predicate, context) {
     context = context || window;
     var arr = [];
     var l = this.length;
     for (var i = 0; i < l; i++)
       if (predicate.call(context, this[i], i, this) === true) arr.push(this[i]);
     return arr;
   };
   

7. Where(func)

   Array.prototype.Where = function (func) {
       var result = [];
       this.forEach(function (item) {
           if (func(item)) {
               result.push( item );
       });
       return result;
   };
   ...
   

8. Where(lambda)

   Array.prototype.Where = function (lambda) {
       if (typeof (lambda) !== "function")
           throw new Error("lambda must be a function");
       var results = [];
       for (var idx = 0; idx < this.length; idx++) {
           var obj = this[idx];
           if (lambda(obj))
               results.push(obj);
       return results;
   

9. WhereT(lambda, t)

   Array.prototype.WhereT = function (lambda, t) {
       if (typeof (lambda) !== "function")
           throw new Error("lambda must be a function");
       var results = [];
       for (var idx = 0; idx < this.length; idx++) {
           var obj = this[idx];
           if (typeof (obj) !== t)
               throw new Error("array items must be " + t + " types but " + obj + " is a " + typeof (obj));
           if (lambda(obj))
   ...