Here you can find the source of insertAt(index,obj)
/*//from w w w. jav a 2 s .c om insert element at given position in the array, bumping all subsequent members up one index */ Array.prototype.insertAt=function(index,obj){ this.splice(index,0,obj); }
Array.prototype.insertAt = function( index, value ) { var part1 = this.slice( 0, index ); var part2 = this.slice( index ); part1.push( value ); return( part1.concat( part2 ) ); };
Array.prototype.insertAt = function(arg, position){
this.splice(position, 0, arg);
};
Array.prototype.insertAt = function(index, item) { this.splice(index, 0, item); return this; };
Array.prototype.insertAt=function(index,obj){
this.splice(index,0,obj);
Array.prototype.insertAt = function (o, index) { if (index > -1 && index <= this.length) { this.splice(index, 0, o); return true; return false; };