13.08.2020, 10:52, "Claude Pache" <claude.pa...@gmail.com>: >> Le 12 août 2020 à 22:05, Luis - SoftSAT Sistemas >> <l...@softsatsistemas.com.br> a écrit : >> >>>> Le 12 août 2020 à 20:19, Luis - SoftSAT Sistemas >>>> <l...@softsatsistemas.com.br> a écrit : >>>> >>>> In the effort to make PHP a better language i want to ask why not "fix" >>>> nested functions as suggested in >>>> (https://wiki.php.net/rfc/true-nested-function-support) or block their >>>> usage? >>>> The current behavior is a lot unexpected. >>>> >>>> I am new here, sorry if it was already discussed, i can't find a good way >>>> to search the mailing history. >>> >>> Hi, >>> >>> Defining a global function inside another function is not useless. Here is >>> a dummy example: >>> >>> ```php >>> // a.php >>> spl_autoload_register(function ($classname) { >>> if ($classname === 'Foo\\B') >>> require 'foo/b.php'; >>> }) >>> >>> // foo/b.php >>> namespace Foo; >>> >>> class B { >>> // ... >>> } >>> >>> function some_helper(....$args) { >>> // ... >>> } >>> ``` >>> >>> The global function `Foo\some_helper` is defined inside the function used >>> as autoloader. >>> >>> Also, from the RFC: >>> >>>> They exist in the global namespace. >>> >>> I think you meant “They exist in the global scope”? because they are >>> defined in the namespace corresponding to the eventual `namespace` >>> declaration of the file. >>> >>> —Claude >> >> You are right Claude, i wasn't thinking about this use case. >> >> But outside of this use case more problems arise. >> If `foo/b.php` have some global variable and some function that use it the >> function breaks because the global variable will be "included" into current >> scope, while the functions into namespace scope. >> ```php >> //a.php >> function foo() { >> require 'b.php'; >> //var_dump($something); >> } >> >> foo(); >> >> var_dump(bar()); >> >> //b.php >> $something = 10; >> >> function bar() { >> global $something; >> return $something; >> } >> ``` >> I expected the `var_dump(bar());` output to be `int (10)`, but it was >> `NULL`, while if i do `var_dump($something);` from `foo()` it outputs >> `int(10)` as "normally expected". >> Given that "bar()" are at namespace scope, this can be "fixed" changing >> `$something = 10;` to `$GLOBALS['something'] = 10;`, but that doesn't change >> the fact that this behavior are odd and not intuitive. >> >> PS: I known that global variables are a bad thing, it was just an example. >> >> Anyway now i see that changing this will break the auto loader system. >> >> About the RFC you are right, they are wrong about the scope, but the RFC >> aren't mine, i just found it while searching about the subject. >> >> --L. Henrique > About global variables; it is an issue I encountered once upon a time when > refactoring code. The short term solution is to declare the global variables > both in the inner and the outer scope: > > ```php > // b.php > global $something; > > $something = 10; > > function bar() { > global $something; > return $something; > } > ``` > > Functions in PHP have the following characteristics: they are defined > globally, and they don’t inherit variables from their parent scope. On the > other hand, anonymous functions (closures) are available locally, and they > may import variables from their parent scope. Both sort of functions have > their usages. > > About the RFC page: It looks to me like an old abandoned stub. It isn’t even > listed on https://wiki.php.net/rfc > > —Claude
I think it's all clear now, thanks Claude! -- L. Henrique -- PHP Internals - PHP Runtime Development Mailing List To unsubscribe, visit: https://www.php.net/unsub.php
