PHP cwords()

cwords.php

<?php

/**
 * A more robust ucwords()
 */

define( 'UCW_DEFAULTS',   0x1 );
define( 'UCW_MATCHSTART', 0x2 );
define( 'UCW_REVERSE',    0x4 );

function cwords( $name, $target_char = null, $delims = '', $flags = 0x3 ) {
  # At least have an empty string
  $delims = is_string( $delims ) ? $delims : '';

  # Use defaults?
  if ( $flags & UCW_DEFAULTS ) {
    $delims .= '_- .\n\t\r"\'';
  }

  # Fix delimiter characters
  $delims = str_replace( '-', '\-', $delims );

  # Build regex
  $regex  = '~(';
  $regex .= ($flags & UCW_MATCHSTART) ? '^|' : '';
  $regex .= '[' . $delims . '])([^' . $delims . ']?)~';

  # Replace all
  return preg_replace_callback(
    $regex,
    function( $matches ) use ( $target_char, $flags ) {
      $str  = is_null( $target_char ) || empty( $matches[1] )
              ? $matches[1]
              : $target_char;
      $casing = $flags & UCW_REVERSE
                ? 'strtolower'
                : 'strtoupper';
      $str .= $casing( $matches[2] );
      return $str;
    },
    $name );
}