A pattern-matching function in PHP

Question

I'm looking for a function, class or collection of functions that will assist in the process of pattern matching strings as I have a project that requires a fair amount of pattern matching and I'd like something easier to read and maintain than raw preg_replace (or regex period).

I've provided a pseudo example in hopes that it will show what I'm asking.

$subject = '$2,500 + $550 on-time bonus, paid 50% upfront ($1,250), 50% on delivery ($1,250 + on-time bonus).';
$pattern = '$n,nnn';
pattern_match($subject, $pattern, 0);

would return "$2,500".

$subject = '$2,500 + $550 on-time bonus, paid 50% upfront ($1,250), 50% on delivery ($1,250 + on-time bonus).';
$pattern = '$n,nnn';
pattern_match($subject, $pattern, 1);

would return an array with the values: [$2,500], [$1,250], [$1,250]

The function — as I'm trying to write — uses 'n' for numbers, 'c' for lower-case alpha and 'C' for upper-case alpha where any non-alphanumeric character represents itself.

Answer 1

<?php

// $match_all = false: returns string with first match
// $match_all = true:  returns array of strings with all matches

function pattern_match($subject, $pattern, $match_all = false)
{
  $pattern = preg_quote($pattern, '|');

  $ar_pattern_replaces = array(
      'n' => '[0-9]',
      'c' => '[a-z]',
      'C' => '[A-Z]',
    );

  $pattern = strtr($pattern, $ar_pattern_replaces);

  $pattern = "|".$pattern."|";

  if ($match_all)
  {
    preg_match_all($pattern, $subject, $matches);
  }
  else
  {
    preg_match($pattern, $subject, $matches);
  }

  return $matches[0];
}

$subject = '$2,500 + $550 on-time bonus, paid 50% upfront ($1,250), 50% on delivery ($1,250 + on-time bonus).';
$pattern = '$n,nnn';

$result = pattern_match($subject, $pattern, 0);
var_dump($result);

$result = pattern_match($subject, $pattern, 1);
var_dump($result);