Enumerable近辺を理解するために
- bindを把握する。prototype.jsを使わずに必要部分を抜き出してみる。
- 以下をコピペで動作します。(そのはず；)
<script>
Object.extend = function(destination, source){
for(var p in source){
destination[p] = source[p];
}
return destination;
}
Object.extend(Function.prototype, {
bind: function() {
if (arguments.length < 2 && arguments[0] === undefined) return this;
var __method = this, args = $A(arguments), object = args.shift();
return function() {
return __method.apply(object, args.concat($A(arguments)));
}
}
});
function $A(iterable) {
if (!iterable) return [];
if (iterable.toArray) return iterable.toArray();
var length = iterable.length, results = new Array(length);
while (length--) results[length] = iterable[length];
return results;
}
document.write("<pre>");
for(p in Function.prototype){
document.write(p + " : " + Function.prototype[p] + "<hr>");
}
var Nabe = function(dasi){
this.dasi = dasi;
this.say = function(){
alert(this.dasi);
}
}
var fuguchiri = new Nabe('konbu');
alert(typeof fuguchiri.say);
setTimeout(fuguchiri.say, 1000);
setTimeout(fuguchiri.say.bind(fuguchiri), 1000);
</script>
