Question

I have preg_match_all('/[aäeëioöuáéíóú]/u', $in, $out, PREG_OFFSET_CAPTURE);

If $in = 'hëllo' $out is:

array(1) {
[0]=>
  array(2) {
  [0]=>
    array(2) {
      [0]=>
      string(2) "ë"
  [1]=>
  int(1)
}
[1]=>
array(2) {
  [0]=>
  string(1) "o"
  [1]=>
  int(5)
  }
}
}

The position of o should be 4. I’ve read about this problem online (the ë gets counted as 2). Is there a solution for this? I’ve seen mb_substr and similar, but is there something like this for preg_match_all?

Kind of related: Is their an equivalent of preg_match_all in Python? (Returning an array of matches with their position in the string)

Answer 1

PHP doesn’t support unicode very well, so a lot of string functions, including preg_*, still count bytes instead of characters.

I tried finding a solution by encoding and decoding strings, but ultimately it all came down to the preg_match_all function.

About the python thing: a python regex matchobject contains the match position by default mo.start() and mo.end(). See: http://docs.python.org/library/re.html#finding-all-adverbs-and-their-positions