erm/vendor/github.com/lxn/walk/expression.go

51 lines
944 B
Go

// Copyright 2017 The Walk Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// +build windows
package walk
import (
"log"
"reflect"
)
import _ "gopkg.in/Knetic/govaluate.v3"
type Expression interface {
Value() interface{}
Changed() *Event
}
type reflectExpression struct {
root Expression
path string
}
func NewReflectExpression(root Expression, path string) Expression {
return &reflectExpression{root: root, path: path}
}
func (re *reflectExpression) Value() interface{} {
rootVal := re.root.Value()
if rootVal == nil {
return nil
}
_, val, err := reflectValueFromPath(reflect.ValueOf(rootVal), re.path)
if err != nil {
log.Print("walk - reflectExpression.Value - Error: ", err.Error())
}
if !val.IsValid() {
return nil
}
return val.Interface()
}
func (re *reflectExpression) Changed() *Event {
return re.root.Changed()
}