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< ol class = "chapter" > < li class = "chapter-item expanded affix " > < a href = "../index.html" > Go语言圣经< / a > < / li > < li class = "chapter-item expanded affix " > < a href = "../preface.html" > 前言< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1.html" > < strong aria-hidden = "true" > 1.< / strong > 入门< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-01.html" > < strong aria-hidden = "true" > 1.1.< / strong > Hello, World< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-02.html" > < strong aria-hidden = "true" > 1.2.< / strong > 命令行参数< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-03.html" > < strong aria-hidden = "true" > 1.3.< / strong > 查找重复的行< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-04.html" > < strong aria-hidden = "true" > 1.4.< / strong > GIF动画< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-05.html" > < strong aria-hidden = "true" > 1.5.< / strong > 获取URL< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-06.html" > < strong aria-hidden = "true" > 1.6.< / strong > 并发获取多个URL< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-07.html" > < strong aria-hidden = "true" > 1.7.< / strong > Web服务< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch1/ch1-08.html" > < strong aria-hidden = "true" > 1.8.< / strong > 本章要点< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../ch2/ch2.html" > < strong aria-hidden = "true" > 2.< / strong > 程序结构< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../ch2/ch2-01.html" > < strong aria-hidden = "true" > 2.1.< / strong > 命名< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch2/ch2-02.html" > < strong aria-hidden = "true" > 2.2.< / strong > 声明< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch2/ch2-03.html" > < strong aria-hidden = "true" > 2.3.< / strong > 变量< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch2/ch2-04.html" > < strong aria-hidden = "true" > 2.4.< / strong > 赋值< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch2/ch2-05.html" > < strong aria-hidden = "true" > 2.5.< / strong > 类型< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch2/ch2-06.html" > < strong aria-hidden = "true" > 2.6.< / strong > 包和文件< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch2/ch2-07.html" > < strong aria-hidden = "true" > 2.7.< / strong > 作用域< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../ch3/ch3.html" > < strong aria-hidden = "true" > 3.< / strong > 基础数据类型< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../ch3/ch3-01.html" > < strong aria-hidden = "true" > 3.1.< / strong > 整型< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch3/ch3-02.html" > < strong aria-hidden = "true" > 3.2.< / strong > 浮点数< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch3/ch3-03.html" > < strong aria-hidden = "true" > 3.3.< / strong > 复数< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch3/ch3-04.html" > < strong aria-hidden = "true" > 3.4.< / strong > 布尔型< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch3/ch3-05.html" > < strong aria-hidden = "true" > 3.5.< / strong > 字符串< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch3/ch3-06.html" > < strong aria-hidden = "true" > 3.6.< / strong > 常量< / a > < / li > < / ol > < / li > < li class = "chapter-item expanded " > < a href = "../ch4/ch4.html" > < strong aria-hidden = "true" > 4.< / strong > 复合数据类型< / a > < / li > < li > < ol class = "section" > < li class = "chapter-item expanded " > < a href = "../ch4/ch4-01.html" > < strong aria-hidden = "true" > 4.1.< / strong > 数组< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch4/ch4-02.html" > < strong aria-hidden = "true" > 4.2.< / strong > Slice< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch4/ch4-03.html" > < strong aria-hidden = "true" > 4.3.< / strong > Map< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch4/ch4-04.html" > < strong aria-hidden = "true" > 4.4.< / strong > 结构体< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch4/ch4-05.html" > < strong aria-hidden = "true" > 4.5.< / strong > JSON< / a > < / li > < li class = "chapter-item expanded " > < a href = "../ch4/ch4-06.html" > < strong aria-hidd
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2022-08-24 10:48:15 +00:00
< li > < em > KusonStack一站式可编程配置技术栈(Go): < a href = "https://github.com/KusionStack/kusion" > https://github.com/KusionStack/kusion< / a > < / em > < / li >
< li > < em > KCL 配置编程语言(Rust): < a href = "https://github.com/KusionStack/KCLVM" > https://github.com/KusionStack/KCLVM< / a > < / em > < / li >
< li > < em > 凹语言™: < a href = "https://github.com/wa-lang/wa" > https://github.com/wa-lang/wa< / a > < / em > < / li >
2022-08-04 06:59:33 +00:00
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< h2 id = "106-包和命名" > < a class = "header" href = "#106-包和命名" > 10.6. 包和命名< / a > < / h2 >
< p > 在本节中, 我们将提供一些关于Go语言独特的包和成员命名的约定。< / p >
< p > 当创建一个包, 一般要用短小的包名, 但也不能太短导致难以理解。标准库中最常用的包有bufio、bytes、flag、fmt、http、io、json、os、sort、sync和time等包。< / p >
< p > 尽可能让命名有描述性且无歧义。例如, 类似imageutil或ioutilis的工具包命名已经足够简洁了, 就无须再命名为util了。要尽量避免包名使用可能被经常用于局部变量的名字, 这样可能导致用户重命名导入包, 例如前面看到的path包。< / p >
< p > 包名一般采用单数的形式。标准库的bytes、errors和strings使用了复数形式, 这是为了避免和预定义的类型冲突, 同样还有go/types是为了避免和type关键字冲突。< / p >
< p > 要避免包名有其它的含义。例如, 2.5节中我们的温度转换包最初使用了temp包名, 虽然并没有持续多久。但这是一个糟糕的尝试, 因为temp几乎是临时变量的同义词。然后我们有一段时间使用了temperature作为包名, 显然名字并没有表达包的真实用途。最后我们改成了和strconv标准包类似的tempconv包名, 这个名字比之前的就好多了。< / p >
< p > 现在让我们看看如何命名包的成员。由于是通过包的导入名字引入包里面的成员, 例如fmt.Println, 同时包含了包名和成员名信息。因此, 我们一般并不需要关注Println的具体内容, 因为fmt包名已经包含了这个信息。当设计一个包的时候, 需要考虑包名和成员名两个部分如何很好地配合。下面有一些例子: < / p >
< pre > < code > bytes.Equal flag.Int http.Get json.Marshal
< / code > < / pre >
< p > 我们可以看到一些常用的命名模式。strings包提供了和字符串相关的诸多操作: < / p >
< pre > < code class = "language-Go" > package strings
func Index(needle, haystack string) int
type Replacer struct{ /* ... */ }
func NewReplacer(oldnew ...string) *Replacer
type Reader struct{ /* ... */ }
func NewReader(s string) *Reader
< / code > < / pre >
< p > 包名strings并没有出现在任何成员名字中。因为用户会这样引用这些成员strings.Index、strings.Replacer等。< / p >
< p > 其它一些包, 可能只描述了单一的数据类型, 例如html/template和math/rand等, 只暴露一个主要的数据结构和与它相关的方法, 还有一个以New命名的函数用于创建实例。< / p >
< pre > < code class = "language-Go" > package rand // " math/rand"
type Rand struct{ /* ... */ }
func New(source Source) *Rand
< / code > < / pre >
< p > 这可能导致一些名字重复, 例如template.Template或rand.Rand, 这就是这些种类的包名往往特别短的原因之一。< / p >
< p > 在另一个极端, 还有像net/http包那样含有非常多的名字和种类不多的数据类型, 因为它们都是要执行一个复杂的复合任务。尽管有将近二十种类型和更多的函数, 但是包中最重要的成员名字却是简单明了的: Get、Post、Handle、Error、Client、Server等。< / p >
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