nested - Nesting PHP-functions: to what purpose? -

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why php allow nesting functions? 

<?php function foo() {     function bar() {         return "bar";     }     return "foo"; } print foo(); print bar();

.. valid php.

but:

  1. why nesting needed ever?
  2. and if so, why can call bar anywhere (and not, e.g. withing foo(), or trough foo.bar() or such).

i ran today, because forgot closing bracket somewhere, , had 1 many further down. code valid , no errors thrown; started acting weird. functions not being declared, callbacks going berserk , on. feature, , if so, purpose? or idiosyncrasy?

answer: commentor points out duplicate of what php nested functions for.

note order important here; cannot call bar() before calling foo() in example. logic here appears execution of foo() defines bar() , puts in global scope, it's not defined prior execution of foo(), because of scoping.

the use here primitive form of function overloading; can have bar() function perform different operations depending upon version of foo() declares it, assuming of course each different version of foo() indeed defines bar() function.


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