Here you can find the source of contains(x)
Array.prototype.contains = function (x) { return this.indexOf(x) > -1; };
"use strict"; Array.prototype.contains = function(value){ var n = this.length for (var i = 0; i < n; i++){ if (this[i] == value) return true return false
Array.prototype.contains = function(value) { return this.indexOf(value) !== -1; }; Array.prototype.remove = function(value) { var index = this.indexOf(value); if ( index !== -1 ) { this.splice(index, 1); }; ...
Array.prototype.contains = function(value) { for(var i=0; i < this.length; i++) { if(this[i] === value) return true; return false; };
Array.prototype.contains = function (what) { var contains = false; if (typeof what !== 'function') { this.forEach(function (item) { if (contains) return; contains = (item === what); }); return contains; this.forEach(function (item) { if (contains) return; contains = what(item); }); return contains; };
Array.prototype.contains=function(x){ for(i in this){ if((x.city==this[i].city || x.firstName==this[i].firstname || x.lastName==this[i].lastname)) return true; return false;
Array.prototype.containsAll = function(c) { for (var i = c.length - 1; i >= 0; i--) { if (!this.contains(c[i])) { return false; return true; };
Array.prototype.containsAll = function(elements) { for (var i = 0; i < elements.length; i++) { if (!this.contains(elements[i])) { return false; return true; };
Array.prototype.containsAll = function(items) for(var i = 0; i<items.length; i++) { if(this.indexOf(items[i]) == -1) return false; return true; };
Array.prototype.containsAny = function(c) { for (var i = c.length - 1; i >= 0; i--) { if (this.contains(c[i])) { return true; return false; };