In some projects that I work, was added some blocks with this syntax:
var [code, name] = input.split("/");
console.log(code);
console.log(name);
I really like this, is so simple and small. It's true I can do this using other syntax like:
var code_name = input.split("/");
console.log(code_name[0]);
console.log(code_name[1]);
But, some browsers like Google Chrome and Opera dont support this "feature". Somebody know if this is a future feature of JS or is deprecated? In case deprecated, exist some beaultiful alternative to the first case?
Thanks for all.
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2See this answer: stackoverflow.com/a/3422473/218196Felix Kling– Felix Kling2012年03月24日 14:47:39 +00:00Commented Mar 24, 2012 at 14:47
3 Answers 3
See:
Possible to assign to multiple variables from an array?
for a similar discussion - unfortunately no cross browser solution seems to exist at the moment - safer to use a temp variable
Comments
It's not as nice as the code you proposed, but I think it looks pretty good nevertheless, although you do have to make some workarounds:
First of all, the idea is to make a clean syntax for calling this function, such as:
[5,4,3,2,1].list(a,b,c,d,e);
The idea is that a,b,c,d,e are modified by reference.
Since variables are passed as value and only objects are passed by reference, the variables a,b,c,d,e must be objects.
var a=Object(),b=Object(),c=Object(),d=Object(),e=Object();
Once they are objects, you are able to modify their value by reference (as explained here http://sirdarckcat.blogspot.com.ar/2007/07/passing-reference-to-javascript.html)
(function(val){if(val)this.valueOf=this.toSource=this.toString=function(){return val};return val;}).call(myVariable,'MyNewValue')
So, wrapping it up in a "list" function which extends the Array.prototype, I ended up with this:
Array.prototype.list = function(){
for(var i=0;i<this.length;i++){
(function(val){if(val)this.valueOf=this.toSource=this.toString=function(){return val};return val;}).call(arguments[i],this[i])
}
}
So when you call [5,4,3,2,1].list(a,b,c,d,e); you are actually modifying objects by reference (and the result will be an object too).
Here's the full working code:
<!DOCTYPE html>
<html>
<head><title>test</title>
<script type="text/javascript">
Array.prototype.list = function(){
for(var i=0;i<this.length;i++){
(function(val){if(val)this.valueOf=this.toSource=this.toString=function(){return val};return val;}).call(arguments[i],this[i])
}
}
</script>
</head>
<body>
<a id="test" href="#">test</a>
<script type="text/javascript">
var a=Object(),b=Object(),c=Object(),d=Object(),e=Object();
[5,4,3,2,1].list(a,b,c,d,e);
console.log(a,b,c,d,e);
</script>
</body>
</html>
1 Comment
var a={}.It's a likely future feature of ECMAScript, and currently available in Firefox.
http://wiki.ecmascript.org/doku.php?id=harmony:destructuring