Sorry, fixed (you get the idea, anyway, doing 10 concats is worse than doing five of them, with _big_ chunks of data in the last calls). There is a checking throw in the end so it really works now.
Now it is even more faster :-)

Herby

-----Pôvodná správa----- From: felix
Sent: Tuesday, January 03, 2012 2:30 PM
To: Herby Vojčík
Cc: Rick Waldron ; Adam Shannon ; Mariusz Nowak ; [email protected]
Subject: Re: Suggestion: Array.prototype.repeat

repeatD(10) returns 17 copies, not 10.

On Tue, Jan 3, 2012 at 4:28 AM, Herby Vojčík <[email protected]> wrote:
Hello,

binary ftw. See http://jsperf.com/array-repeat/4 Array.prototype.repeatD.
And I also tried push.apply in repeatC (not to copy over the array using
concat but grow it in place until possible) and it really surprised me it
was that much slower. Concat is probably heavily optimized.

Herby

-----Pôvodná správa----- From: Rick Waldron
Sent: Tuesday, January 03, 2012 2:21 AM
To: Adam Shannon
Cc: [email protected] ; Mariusz Nowak
Subject: Re: Suggestion: Array.prototype.repeat





On Mon, Jan 2, 2012 at 5:55 PM, Adam Shannon <[email protected]> wrote:
Another thing to think about is that .repeat (both on String and
Array) will be used a lot in production. So it would make sense for
each solution to be optimized for their specific case. It doesn't make
sense to slow down something as trivial as .repeat()


Creating a 10000 item array by repeating a 1000 item array 10 times, the
difference is negligible when compared the implementation that I wrote, not
the one given above

http://jsperf.com/array-repeat/2

Also, note that I had to "make up" my own Array.repeat() because the
Array.generate shown above did not create the same return as the initial
Array.prototype.repeat(), but I stuck to the concepts laid out - no new
array is initialized (except that Array.prototype.slice _does_ initialize a
new Array() ).

Rick


_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss

_______________________________________________
es-discuss mailing list
[email protected]
https://mail.mozilla.org/listinfo/es-discuss

Reply via email to