New ES6 strawman: Array.prototype.fill and Array.prototype.move

Brendan Eich brendan at
Sun Jun 23 13:36:03 PDT 2013

Allen Wirfs-Brock wrote:
> See 
> for a strawman proposal for two new Array methods. These are proposed 
> for inclusion in ES6.

I updated the wiki:


Q: Does anyone know of a rationale for why (start, end) might be a 
better design pattern than (start, count) for such operation?

A: Array.prototype.slice uses (start, end) where end is a fencepost to 
facilitate looping over half-open ranges within a larger range. Spec’ing 
count requires subtracting next_start - end, gratuitously. Also, 
consistency with slice and range APIs matters. This should be considered 
carefully in the design.

— /Brendan Eich 
2013/06/23 20:31/


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