How to efficiently insert elements after another known (by key or pointer) element in a PHP array?

Question

Given an array:

$a = array(
    \'abc\',
    123,
    \'k1\'=>\'v1\',
    \'k2\'=>\'v2\',
    78,
    \'tt\',
    \'k3\'=>\'v3\'
);

Wi

Answer 1

This way is fine for new values without keys. You can not insert value with a key, and numeric indexes will be 'reset' as 0 to N-1.

$keys = array_keys($a);
$index = array_flip($keys);

$key = key($a); //current element
//or 
$key = 'k1';

array_splice($a, $index[$key] + 1, 0, array('value'));