code: function detachProps(rule) {
      var rs = {};
      var params = removeSpace(rule.params);
      var argsRE = /\(\S+\)/g;
  
      var name = detachCustomName(params);
  
      var args = detachCustomValues(params);
  
      var content = removeSpace(rule.nodes[0].params);
  
      rs.name = name;
      rs.args = args;
      rs.content = content;
      return rs;
  }
docs: [detach props from function definition]
  @param  {[String]} rule [Postcss Rule]
  @return {[Object]}
  
  @define-function rem($val) {@return $val / 640 * 10 * 1rem} => {name: 'rem', args: ['$val'], content: '$val / 640 * 10 * 1rem'}