Re: Improvements to for-each implementation

Hi Nikita, I would suggest using the proposal for the by-value case and sticking with the current behavior for the by-reference case as you suggested. Granted, we then cannot remove the internal pointer all together, but we would just use it for the less common by-reference case as well as for the legacy reset/next functions, of course. This would still improve most for-each traversals. At least we then wouldn't have to find a replacement solution for rest/prev/next/end. Moreover we can then move the internal position pointer out of the hashtable structure into zend_array because it is only used for userland arrays, not other hash tables (such as object properties or internal structures that build upon the hashtable struct). Thanks, Ben ========== Original ========== From: Nikita Popov <nikita.ppv@gmail.com> To: Benjamin Coutu <ben.coutu@zeyos.com> Date: Thu, 22 Jan 2015 10:53:19 +0100 Subject: Re: [PHP-DEV] Improvements to for-each implementation Doing this was the idea I had in mind as well, i.e. change the semantics of foreach to say that it will always work on a copy for by-value iteration (which ironically avoids having to actually copy it). Note that this will differ from the current behavior in a number of ways. In particular it means that changes to arrays that were references prior to iteration will not influence the iteration. The real question is what we should do in the by-reference case. Given that we need to acquire references to elements of the original array we can't reasonably work with copy-semantics (at least I don't see how). So would we just stick with the previous behavior (using the hash position hack) for that? Nikita