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

Hi, On 15 Sep 2017 19:37, <ilija.tovilo@me.com> wrote: Hi Marco I can see it’s usefulness in this case. But wouldn’t it be better to implement this by hand in these rare cases (it’s 3 lines of code) instead of encouraging the pollution of the symbol table by unknown input? It’s also clearer since people who don’t know the extract function probably don’t expect it to mutate the local symbol table. Cheers On 15 Sep 2017, 19:26 +0200, Marco Pivetta <ocramius@gmail.com>, wrote: Heya, This is typically used in templating engines. The one I worked on is https://github.com/zendframework/zend-view/blob/ 5523511b6771cb6c060a77f6777426526a8db5ab/src/Renderer/ PhpRenderer.php#L491-L492 Marco Pivetta http://twitter.com/Ocramius http://ocramius.github.com/ On Fri, Sep 15, 2017 at 7:20 PM, <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? Regards Absolutely, can be replaced with a loop indeed.