Re: [RFC] Deprecate the extract function in PHP 7.3

On Fri, Sep 15, 2017 at 11:38 AM, <ilija.tovilo@me.com> wrote: > Hi Ryan > > I can see your argument. The reasoning behind it is that a function in the > standard library should not encourage unsafe code. Admittedly, since this > function is rarely used except for templating systems one could call this a > non-issue. I just wanted to bring it up. > That makes sense. What about performance difference? On a reasonable sized array (not 10k items and not 2) which is faster? extract($array); - or - foreach ($array as $key => $value) $$key = $value; Honestly, I don't know (ps 2 lines without braces instead of 3!) > > Regards > > > On 15 Sep 2017, 19:30 +0200, Ryan Pallas <derokorian@gmail.com>, wrote: > > > > On Sep 15, 2017 11:22 AM, <ilija.tovilo@me.com> wrote: > > Hi! > > The extract function takes an associative array and puts it > into the > local symbol table. > http://php.net/manual/en/function.extract.php > > ``` > $array = [ > ‘foo’ => ‘foo’, > ‘bar’ => ‘bar’, > ]; > > extract($array); > > print $foo; // "foo" > ``` > > As a second parameter the extract function takes some options > to make > this function less dangerous, like EXTR_SKIP that prevents an > existing > local variable of being overwritten. There’s a few more options, go ahead > and take a look at the documentation. EXTR_OVERWRITE is the > default one > though. You can also pass a prefix for the variable names as a third > argument. > > I seriously doubt the usefulness of this function, especially looking at > the potential risks. The fact that overwriting the local variables is the > default behaviour doesn’t make it any better. I suggest deprecating it in > PHP 7.3 and removing it in 8. > > In a whole Symfony-Stack (3.4) with all of it’s dependencies I could only > find two usages of this function, both of which could be easily rewritten > in vanilla PHP: > https://github.com/symfony/symfony/blob/master/src/Symfony/ > Component/Templating/PhpEngine.php#L148 > https://github.com/symfony/symfony/blob/master/src/Symfony/ > Component/Templating/PhpEngine.php#L158 > > Only downside: A polyfill is probably impossible since you cannot mutate > the local symbol table of the callee (as far as I’m aware). > > Any thoughts? > > > I see no gain by removing this function. I've also seen it used for > templating quite often. Yes the functionality could be changed not to use > extract and end up working the same to the consumer but why make people > rewrite these things for no apparent gain (and likely a small performance > hit)? > > > Regards > > > >