Argument unpacking?

Brendan Eich brendan at
Thu Nov 9 13:35:53 PST 2006

I should mention that destructuring formal parameters allow the  
function to take an array actual parameter and bind its elements to  
named formal parameters:

function f(a, [b, c]) { print(a, b, c); }
f(1, [2, 3]) // prints "1 2 3"

This is different yet again.  I wanted to point it out in case it was  
missed (it wasn't specified in the first wiki dump, IIRC).  It's  
implemented in JS1.7 in Firefox 2.


On Nov 9, 2006, at 1:29 PM, Brendan Eich wrote:

> No plans.  Function.prototype.apply is still there, albeit not as  
> powerful or convenient.
> I'm still hoping for something in ES4 that makes apply universal  
> (it doesn't work on alert in IE; this should not be allowed by the  
> spec by leaving it up to "host objects" to be broken if they ought  
> to delegate to Function.prototype).  It would also be helpful for  
> bootstrapping if new and apply could be composed; this came up when  
> I wrote Narcissus.  Suggestions?
> /be

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