code: def t_php_STRING(t):
      r'[A-Za-z_][\w_]*'
      t.type = reserved_map.get(t.value.upper(), 'STRING')
      return f t_php_STRING(t):
      r'[A-Za-z_][\w_]*'
      t.type = reserved_map.get(t.value.upper(), 'STRING')
      return t
docs: r'[A-Za-z_][\w_]*