Array.prototype.each = function(fn){
	return this.length? [fn(this[0])].concat(this.slice(1).each(fn)): [];
};
//e.g.
var arr = [1,2,3,4].each(function(x){return x*2;});
//alert(arr);//[2,3,6,8]

Array.prototype.each = function(fn){
		return this.length? [fn(this[0])].concat(this.slice(1).each(fn)): [];
	};
        //e.g.
	var arr = [1,2,3,4].each(function(x){return x*2;});
	//alert(arr);//[2,3,6,8]

each in Array,It can operate each element in Array.
e.g.
var result = [1,2,3,4].each(function(x){return Math.sqrt(x);});
//it return sqrt in [1,2,3,4]'s each item

currying in javascript

javascript

JavaScript