prototype.js分析 Enumerable

JavaScript

max() 要素の最大値を取得する

<script>
Array.prototype._each = function(iterator){
	for(var i=0, l=this.length; i<l; i++){
		iterator(this[i]);
	}
};

Array.prototype.each = function(iterator){
	var index = 0;
	try{
		this._each(function(v){
			iterator(v, index++);
		});
	} catch(e){
		if(e != $break) throw e;
	}
};

Array.prototype.max = function(iterator){
	var iterator = iterator || function(x){return x};
	var rs;
	this.each(function(v, k){
		v = iterator(v, k);
		if(rs == undefined || v >= rs)
			rs = v;
	});
	return rs;
};

var kekka = [1,2,3,4,5,4,12,3,2].max();
console.log(kekka);
</script>