I'm wondering if anyone knows why call
is so much faster than apply
? In chrome, it's roughly 4x faster, and 30x in firefox, and I can even make a custom prototype, apply2
, that does (in most cases) run 2x as fast as apply
(the idea taken from angular):
Function.prototype.apply2 = function( self, arguments ){
switch( arguments.length ){
case 1: this.call( self, arguments[0] ); break;
case 2: this.call( self, arguments[0], arguments[1] ); break;
case 3: this.call( self, arguments[0], arguments[1], arguments[2] ); break;
case 4: this.call( self, arguments[0], arguments[1], arguments[2], arguments[3] ); break;
case 5: this.call( self, arguments[0], arguments[1], arguments[2], arguments[3], arguments[4] ); break;
case 6: this.call( self, arguments[0], arguments[1], arguments[2], arguments[3], arguments[4], arguments[5] ); break;
case 7: this.call( self, arguments[0], arguments[1], arguments[2], arguments[3], arguments[4], arguments[5], arguments[6] ); break;
case 8: this.call( self, arguments[0], arguments[1], arguments[2], arguments[3], arguments[4], arguments[5], arguments[6], arguments[7] ); break;
case 9: this.call( self, arguments[0], arguments[1], arguments[2], arguments[3], arguments[4], arguments[5], arguments[6], arguments[7], arguments[8] ); break;
case 10: this.call( self, arguments[0], arguments[1], arguments[2], arguments[3], arguments[4], arguments[5], arguments[6], arguments[7], arguments[8], arguments[9] ); break;
default: this.apply( self, arguments ); break;
}
};
So does anyone know why?