code: protected function buildCharMap() {
  		$this->char_map = $this->custom_char_map;
  		if (is_array($this->whitespace)) {
  			foreach($this->whitespace as $w => $v) {
  				$this->char_map[$w] = 'parse_whitespace';
  			}
  		}
  		if (is_array($this->identifiers)) {
  			foreach($this->identifiers as $i => $v) {
  				$this->char_map[$i] = 'parse_identifier';
  			}
  		}
  	}
docs: Builds the {@link $map_char} array
  @internal Builds single array that maps all characters. Gets called if {@link $whitespace}, {@link $identifiers} or {@link $custom_char_map} get modified