英文:
May a New function allocate filedescriptors in Golang
问题
由于我是一个中文翻译助手，我将为您翻译以下内容：
由于我来自C和C++的背景，而golang在语义上有所不同，所以我对函数名称“New”与“Open”有一些讨论，以及程序员对底层操作的期望。我创建了一个包，其中的New函数打开了临时文件的文件描述符。我不确定这是否是Go语言中API的预期行为。
以下是代码片段：
// 直接使用New不太方便，它会分配文件描述符
deb := New()
deb.AddFile("/tmp/myfile")
deb.Write("/tmp/mypackage.deb")
deb.Close()
// 惯用法是它打开文件描述符，但我们需要提供上下文来打开
info := &Props{Name: "mypackage"}
deb := info.Open("/tmp/mypackage.deb")
deb.AddFile("/tmp/myfile")
deb.Close()
希望对您有所帮助！
英文:
As I come from a C and C++ background and golang is semantically different I have some discussions about function names "New" vs "Open" and what the programmer expects what to happen under the hood. I have created a package where the New function opens file descriptors to temporary files. I'm not sure this is intended behavior for APIs written in Go.
Here is a snippet:
<!-- language: lang-golang -->
// Not directly convenient New allocates file descriptors
deb := New()
deb.AddFile("/tmp/myfile")
deb.Write("/tmp/mypackage.deb")
deb.Close()
// Idiomatic it opens file descriptors but we have to provide context to open
info := &Props{Name: "mypackage"}
deb := info.Open("/tmp/mypackage.deb")
deb.AddFile("/tmp/myfile")
deb.Close()
答案1
得分: 2
Go的社区仍在寻找其惯用语和模式，所以不要认为任何东西都是教条。根据我在一年半的时间里所见，如果在New函数中有godoc注释解释其行为，我认为在函数中涉及磁盘操作并不是错误的。这可能是不寻常的，可能更合理的做法是在d.Write()中涉及磁盘操作。我见过一些常见的New函数模式：
- 只有在设计供其他包使用时才会导出
- 当从其他包中调用时，使用包名前缀是有意义的：
d := deb.New(...)（由于你有一个名为deb的变量，你的包可能是其他东西） - 返回包的主要业务逻辑的实例，以供进一步使用
- 将依赖项作为参数接受，而不是构建自己的依赖项（希望任何行为依赖项都是接口）
- 通常一个
main()函数组装这些依赖项，调用d := deb.New(deps)，并执行行为d.AddFile(); d.Write(); d.Close()
使用接口的示例签名：
package deb
// New接受blah并返回*Deb。如果blah，则返回nil。
func New(name string, to io.WriteCloser) *Deb {...}
英文:
Go's community is still finding its idioms and patterns, so don't consider anything dogma. Based on what I've seen in a year and a half, I don't think it's wrong to touch disk in a New function if it has godoc comments explaining the behavior. It would be unusual, and probably make more sense to touch the disk in d.Write(). Some common patterns I've seen with New functions:
- are only exported when designed for use by other packages
- makes sense when invoked from other packages with the package name prefixed:
d := deb.New(...)(since you have a variable nameddeb, your package is something else) - returns an instance of the package's main business logic, to be used further
- accept dependencies as arguments instead of constructing its own dependencies (hopefully any behavioral dependencies are interfaces)
- often a
main()function assembles those dependencies, callsd := deb.New(deps), and executes the behaviord.AddFile(); d.Write(); d.Close()
an example signature using an interface:
package deb
// New accepts blah returning a *Deb. It returns nil if blah.
func New(name string, to io.WriteCloser) *Deb {...}
通过集体智慧和协作来改善编程学习和解决问题的方式。致力于成为全球开发者共同参与的知识库，让每个人都能够通过互相帮助和分享经验来进步。
评论