array_map inline anonymous function

Question

I tested inline anonymous function with array_map here

and it worked but when I tried same with $user_meta it is not working.

$user_meta = Array ( [interest] => Array ( [0] => Array ) [type] => 
     Array ( [0] => Array ) [user_status] => Array ( [0] => deny)
     [firstname] => Array ( [0] => ) [lastname] => Array ( [0] => B ) 
     [email] => [email protected] ) 

$user_meta = array_map(function($a) { return $a[0]; },$user_meta);

"Parse error: syntax error, unexpected T_FUNCTION, expecting ')' in"

here is the test link showing error

Answer 1

I hope this will help:

$user_meta = array_map(function ($a) { return $a[0]; }, $user_meta);

Answer 2

There's nothing wrong with the array_map line, but everything before it is wrong. That is the output of a print_r not PHP code. Compare how you define the array in the two links you posted.

Answer 3

Slightly shorter could be

$user_meta = array_map(fn ($a) => $a[0], $user_meta);

But I would prefer the array_column approach for such an array_map