Question

Given the following PHP code:

<?php
$str = '/foo/bar/baz';
preg_match('#^(/[^/]+?)*$#', $str, $matches);
var_dump($matches);

…I’m getting the following output:

array (size=2)
  0 => string '/foo/bar/baz' (length=12)
  1 => string '/baz' (length=4)

…but I don’t understand why. I would expect each match of (/[^/]+?) to be captured into its own group and stuck into $matches, such that it looked like this instead:

array (size=4)
  0 => string '/foo/bar/baz' (length=12)
  1 => string '/foo' (length=4)
  2 => string '/bar' (length=4)
  3 => string '/baz' (length=4)

What am I missing?

Edit:

This is the output if I use preg_match_all() instead, which still isn’t what I’m looking for:

array (size=2)
  0 => 
    array (size=1)
      0 => string '/foo/bar/baz' (length=12)
  1 => 
    array (size=1)
      0 => string '/baz' (length=4)

Answer 1

This is the standard behavior of repeated capture groups — they match all the repetitions, but only capture the last one. See Can Regex groups and * wildcards work together? for a similar question using Python. I tried it in Perl and got the same result.