code: func (v *evalVisitor) helperOptions(node *ast.Expression) *Options {
  	var params []interface{}
  	var hash map[string]interface{}
  
  	for _, paramNode := range node.Params {
  		param := paramNode.Accept(v)
  		params = append(params, param)
  	}
  
  	if node.Hash != nil {
  		hash, _ = node.Hash.Accept(v).(map[string]interface{})
  	}
  
  	return newOptions(v, params, hash)
  }
docs: // helperOptions computes helper options argument from an expression