698900 - Implement Array.prototype.* methods with unfixed number of parameters with rest parameters

Status: RESOLVED INCOMPLETE

(Core :: JavaScript Engine, enhancement)

Description

[David Bruant]

It seems (https://mail.mozilla.org/pipermail/es-discuss/2011-July/016124.html) that JS stack suffers when doing something like Array.prototype.push.apply(a1, a2) if a2 is to big of an array.
One idea would to stop thinking as Array.prototype.push as a method with a lot of arguments, but rather think it as Array.prototype.push(...items) (as per "rest parameters"). For any number of elements, there would only be one element in the stack.

Comment 1

[Matthew Gaudet (he/him) [:mgaudet]]

It's unclear what the actual concrete concern is here, and it's been 13 years.

Comment 2

[Iain Ireland [:iain]]

Reading between the lines, I suspect that the reporter had learned that fn.apply(..., arr) will push every element of arr to the stack (potentially using a lot of stack space for large arrays) and wanted to suggest an alternative. However, the alternative has the same problem: spread calls have the same behaviour as apply, and in fact share a bunch of code under the covers.