Re: Idea: ifdef-like feature to ease userland BC

On 08.03.2014, at 22:48, Marco Schuster <marco+php@m-s-d.eu> wrote: > $var=[];, traits or similar Neither of these is something you'd really do a version switch around, as it would lead to a lot of duplicated code, that needs to be kept in sync. Of the top of my head there are three situations where branching based on the PHP version is necessary/useful: 1. I'm using an API which is deprecated/unavailable in the newer version I support but the replacement is not available in the older version. 2. I can improve performance, security or functionality by using some new native function that is not available in the newer version. (For example hex2bin only being available in PHP >= 5.4) 3. Working around bugs in specific PHP versions. It would be incredibly unlikely for any of these to involve recently improved syntax. Also note that from what I'm understanding the OPCache Optimizer will actually remove some branches which can't be called, so there's some chance that there will be no runtime performance impact at all by these checks. Best regards Rouven