Comments on: Duck Typing on JavaScript, and getter/setter

By: beatak

beatak — Tue, 25 Nov 2008 23:56:09 +0000

I’m not 100% sure what Daniel means by that code… it looks like a using String as Array-like access? It should work if you fix as below, but I think it less efficient.

var c = function(a, len) { if (len > 0) { return a[len].join( c(a, len - 1) ); } else { return a[0]; } }; var string = c(target, target.length);

By: Daniel

Daniel — Tue, 25 Nov 2008 23:36:33 +0000

What about a recursive function? I’m not familiar with javascript (so this is probably not valid syntax), but the concatenation function could potentially look like:

var string = (c: function(a, len) {if (len > 0) {return a[len].join(c(a, len – 1));} else {return a[0];}});

By: beatak

beatak — Fri, 31 Oct 2008 23:23:55 +0000

What I really think interesting about is that this is somehow tricky and you don’t have to know to do the things in JavaScript (unless you need a speed), but on the other hand it gives such a simplicity and potential. Thanks for letting me know!

By: Mauvis

Mauvis — Fri, 31 Oct 2008 17:11:45 +0000

In hindsight there was no reason for me to use a closure in my response and it should have been more like:

function concatenate(){
var string = Array.prototype.slice.call(arguments).join(”);
return string;
}

Still the third response is better since we’re just borrowing the join prototype off the Array object instead of converting the arguments object to an array and then calling it’s join method.

Nice writeup!