CODEWITHSUNDEEP
php
tmountjr
tmountjr

Reputation: 1475

array_map with an array of variable names

How can I use array_map to transform an array of variable names into an array of the values of those names? For example:

$arg_array = array('foo', 'bar');
$foo = "asdf";
$bar = "qwer";

print_r(array_map(function($a) {return ${$a};}, $arg_array)); //doesn't work

var_dump(${$arg_array[0]}); //works

Seems like it should be straightforward, but the array_map function returns Undefined variable: foo and Undefined variable: bar, then shows an array of ''.

Upvotes: 1

Views: 265

Answers (1)

Lajos Veres
Lajos Veres

Reputation: 13725

I think this is a scoping issue.

Adding a global ${$a} will help:

print_r(array_map(function($a) {global ${$a};return ${$a};}, $arg_array)); //doesn't

At least if the outer block is the global namespace...

Otherwise this kind of creating names of variables dynamically is not a good sign... This cases are generally convertible to arrays, and the life is much easier with arrays.

Upvotes: 2

Related Questions