dsgk0386 2017-12-31 23:10
浏览 102
已采纳

Golang使用嵌入式模板初始化结构:结构初始化程序中的值太少

I'm trying to initialize a golang struct with an embedded template. Since templates have no fields, I would expect that assigning the correct number of variables to a constructor would work, but instead the compiler complains that

main.go:17:19: too few values in struct initializer

package main

import "fmt"

type TestTemplate interface {
    Name() string
}

type TestBase struct {
    name       string

    TestTemplate
}

func New(name string) *TestBase {
    return &TestBase{name} // This fails
    //return &TestBase{name: name} // This works
}

func (v *TestBase) Name() string {
    return v.name
}

func main() {
    fmt.Println(New("Hello"))
}
  • 写回答

2条回答 默认 最新

  • dongshi2141 2017-12-31 23:59
    关注

    https://golang.org/ref/spec#Struct_types

    An embedded field is still a field, the name of which is derived from its type, therefore TestBase has actually two fields and not one, namely name and TestTemplate.

    This compiles just fine:

    var t *TestBase
    t.TestTemplate.Print()
    

    So when initializing TestBase you either specify the field names or you initialize all fields.

    These all compile:

    _ = &TestBase{name, nil}
    _ = &TestBase{name: name}
    _ = &TestBase{name: name, TestTemplate: nil}
    _ = &TestBase{TestTemplate: nil}
    
    本回答被题主选为最佳回答 , 对您是否有帮助呢?
    评论
查看更多回答(1条)

报告相同问题?

悬赏问题

  • ¥20 sub地址DHCP问题
  • ¥15 delta降尺度计算的一些细节,有偿
  • ¥15 Arduino红外遥控代码有问题
  • ¥15 数值计算离散正交多项式
  • ¥30 数值计算均差系数编程
  • ¥15 redis-full-check比较 两个集群的数据出错
  • ¥15 Matlab编程问题
  • ¥15 训练的多模态特征融合模型准确度很低怎么办
  • ¥15 kylin启动报错log4j类冲突
  • ¥15 超声波模块测距控制点灯,灯的闪烁很不稳定,经过调试发现测的距离偏大