On Tue, Feb 24, 2015 at 2:37 PM, Nikita Popov <nikita....@gmail.com> wrote:
> On Mon, Feb 23, 2015 at 10:36 PM, Nikita Popov <nikita....@gmail.com> > wrote: > > > Hi internals! > > > > With regard to my E_STRICT RFC [1] Yasuo and another off-the-record mail > > expressed a concern about the "Only variables should be passed by > > reference" strict standards warning. > > > > This notices makes sense in a lot of places, e.g. > > > > array_push(getArray(), 1, 2, 3); > > > > is totally pointless code if getArray() doesn't return a reference. > > array_push will just modify a temporary array in this case. > > > > However other usages like > > > > $top = array_pop(getArray()); > > > > are less clear: array_pop() both has a side-effect (removing the top > > element of an array) and a meaningful return value (the top element of > the > > array). As PHP does not have a dedicated function for getting the > > first/last element of an array, many people use code like this (which > > currently throws E_STRICT) instead. > > > > I'd like to mark a few such functions with PREFER_REF (i.e. allow passing > > both references and values). In particular array_pop() and array_shift(). > > > > Does anybody have a problem with us doing this? Are there other functions > > which should use PREFER_REF? > > > > The motivation behind this is to make sure we only throw this notice in > > cases where the code is actually buggy/nonsensical instead of just making > > people ignore it altogether. > > > > A few people have pointed out OTR that the same applies to reset() and > end(). Both can be used to get the first/last element (and change the IAP > as a side effect). So I'd add PREFER_REF to those as well. (Interestingly > key() and current() already use PREFR_REF even though they don't modify the > array at all, probably this is a performance optimization.) > key() and current() shouldn't use it. It was an optimization from PHP5 time that makes for PHP-7 more harm than benefit. According to array_pop(), array_shift(), reset() and end(), it's not a problem to avoid this warning. But note that such usage of these functions may be really inefficient, because they may need to duplicate the passed array first. Thanks. Dmitry. > > Nikita >
