PHP version of: https://github.com/nex3/sass/blob/master/lib/sass/scss/rx.rb#L49

gistfile1.aw

<?php

      $H = '[0-9a-fA-F]';
      $NL = '\n|\r\n|\r|\f';
      $UNICODE = '\\\\' . $H . '{1,6}[ \t\r\n\f]?';
      $s = '\x{80}-\x{D7FF}\x{E000}-\x{FFFD}\x{10000}-\x{10FFFF}';
      //$s = '\X'; // tmp
      $NONASCII = '[' . $s . ']';
      $ESCAPE = $UNICODE . '|\\[ -~' . $s . ']';
      $NMSTART = '[_a-zA-Z]|' . $NONASCII . '|' . $ESCAPE;
      $NMCHAR = '[a-zA-Z0-9_-]|' . $NONASCII . '|' . $ESCAPE;
      $STRING1 = '\"((?:[^\n\r\f\\"]|\\' . $NL . '|' . $ESCAPE . ')*)\"';
      $STRING2 = "\'((?:[^\n\r\f\\']|\\" . $NL . '|' . $ESCAPE . ")*)\'";

      $IDENT = '-?' . $NMSTART . $NMCHAR . '*';
      $NAME = $NMCHAR . '+';
      $NUM = '[0-9]+|[0-9]*\.[0-9]+';
      $STRING = $STRING1 . '|' . $STRING2;
      $URLCHAR = '[#%&*-~]|' . $NONASCII . '|' . $ESCAPE;
      $URL = '(' . $URLCHAR . '*)';
      $W = '[ \t\r\n\f]*';
      $VARIABLE = '(\$)(' . $IDENT . ')';

      $RANGE = '(?:' . $H . '|\?){1,6}';

      $S = '[ \t\r\n\f]+';

      $COMMENT = '\/\*[^*]*\*+(?:[^\/][^*]*\*+)*\/';
      $SINGLE_LINE_COMMENT = '\/\/.*(\n[ \t]*\/\/.*)*';

      $CDO = preg_quote('<!--');
      $CDC = preg_quote('-->');
      $INCLUDES = preg_quote('~=');
      $DASHMATCH = preg_quote('|=');
      $PREFIXMATCH = preg_quote('^=');
      $SUFFIXMATCH = preg_quote('$=');
      $SUBSTRINGMATCH = preg_quote('*=');

      $HASH = '#' . $NAME;

      $IMPORTANT = '(?i:!' . $W . 'important)';
      $DEFAULT = '!(?i:' . $W . 'default)';

      $NUMBER = $NUM . '(?:' . $IDENT . '|%)?';

      $URI = '(?i:url\(' . $W . '(?:' . $STRING . '|' . $URL . ')' . $W . '\))';
      $FUNCTION = $IDENT . '\(';

      $UNICODERANGE = '(?i:u\+(?:' . $H . '{1,6}-' . $H . '{1,6}|' . $RANGE . '))';

      $PLUS = $W . '\+';
      $GREATER = $W . '>';
      $TILDE = $W . '~';
      $NOT = preg_quote(":not(");

      $HEXCOLOR = '\#[0-9a-fA-F]+';
      $INTERP_START = '#\{';
      $ANY = '(?i::(-[-\w]+-)?any\()';

      $STRING1_NOINTERP = '\"((?:[^\n\r\f\\"#]|#(?!\{)|\\' . $NL . '|' . $ESCAPE . ')*)\"';
      $STRING2_NOINTERP = "\'((?:[^\n\r\f\\'#]|#(?!\{)|\\" . $NL . '|' . $ESCAPE . ")*)\'";
      $STRING_NOINTERP = $STRING1_NOINTERP . '|' . $STRING2_NOINTERP;

      $STATIC_VALUE = '(?i:(-?' . $NMSTART . '|' . $STRING_NOINTERP . '|\s(?!%)|#[a-f0-9]|[,%]|' . $NUM . '|\!important)+(?=[;}]))';

      $STATIC_SELECTOR = '(?i:(' . $NMCHAR . '|\s|[,>+*]|[:#.]' . $NMSTART . ')+(?=[{]))';


var_dump('/' . $IDENT . '/u');
var_dump(preg_match_all('/' . $IDENT . '/u', ' $drtjsyj: 3467;', $matches), $matches);