go - 在结构上设置字段丢失？

Question

type Project struct {
    ID   int    `json:"id"`
    Name string `json:"name"`
}

type Commit struct {
    ID            string `json:"id"`
    Message       string `json:"message"`
    CommitterName string `json:"committer_name"`
    CommittedDate string `json:"committed_date"`
    Project       Project
}

func (c *Commit) SetProject(project Project) {
    c.Project = project
}

var commits []Commit // pre-populated list of commits

// goroutine 1
for _, commit := range commits {
  fmt.Println(project) // this prints out with the expected result
  commit.SetProject(project)
  fmt.Println(commit) // this prints out with the expected result
}
ch <- commits

// goroutine 2
for commits := range ch {
  fmt.Println(commits[0].Project) // => {0 }, project is not there
}

如何在提交上设置项目？

Answer 1

根据您的描述，看来commits的类型为[]Commit。如果是这种情况，则for循环中的commit是数组元素的副本，对其进行更改将更改该副本，而不是数组中的Commit。因此，使用索引访问并修改数组中的提交:

for i, _ := range commits {
    commits[i].SetProject(project)
}