Go例子和成语

Question

没有太多的Go语言代码可用于学习该语言，而且我敢肯定，我并不是唯一一个尝试过该语言的人。因此，如果您发现有关该语言的一些有趣信息，请在此处发布示例。

我也在寻找

• Go中惯用的方式来做事，

• C / C ++思维风格“移植”到Go，

• 有关语法的常见陷阱，

• 真的很有趣。

Answer 1

推迟陈述“ defer”语句调用一个函数，该函数的执行被推迟到周围函数返回的那一刻。DeferStmt =“ defer”表达式。表达式必须是函数或方法调用。每次执行“ defer”语句时，都会对函数调用的参数进行评估并重新保存，但不会调用该函数。延迟的函数调用将在周围函数返回之前立即以LIFO顺序执行，但是在对返回值（如果有）进行求值之后才执行。lock(l);defer unlock(l);&nbsp; // unlocking happens before surrounding function returns// prints 3 2 1 0 before surrounding function returnsfor i := 0; i <= 3; i++ {&nbsp; &nbsp; defer fmt.Print(i);}更新：defer现在也处理惯用方式panic在例外样方式：package mainimport "fmt"func main() {&nbsp; &nbsp; f()&nbsp; &nbsp; fmt.Println("Returned normally from f.")}func f() {&nbsp; &nbsp; defer func() {&nbsp; &nbsp; &nbsp; &nbsp; if r := recover(); r != nil {&nbsp; &nbsp; &nbsp; &nbsp; &nbsp; &nbsp; fmt.Println("Recovered in f", r)&nbsp; &nbsp; &nbsp; &nbsp; }&nbsp; &nbsp; }()&nbsp; &nbsp; fmt.Println("Calling g.")&nbsp; &nbsp; g(0)&nbsp; &nbsp; fmt.Println("Returned normally from g.")}func g(i int) {&nbsp; &nbsp; if i > 3 {&nbsp; &nbsp; &nbsp; &nbsp; fmt.Println("Panicking!")&nbsp; &nbsp; &nbsp; &nbsp; panic(fmt.Sprintf("%v", i))&nbsp; &nbsp; }&nbsp; &nbsp; defer fmt.Println("Defer in g", i)&nbsp; &nbsp; fmt.Println("Printing in g", i)&nbsp; &nbsp; g(i+1)}

Answer 2

Go对象文件实际上包含明文标题：jurily@jurily ~/workspace/go/euler31 $ 6g euler31.gojurily@jurily ~/workspace/go/euler31 $ cat euler31.6amd64&nbsp; exports automatically generated from&nbsp; euler31.go in package "main"&nbsp; &nbsp; import$$&nbsp; // exports&nbsp; package main&nbsp; &nbsp; var main.coin [9]int&nbsp; &nbsp; func main.howmany (amount int, max int) (? int)&nbsp; &nbsp; func main.main ()&nbsp; &nbsp; var main.initdone· uint8&nbsp; &nbsp; func main.init ()$$&nbsp; // local types&nbsp; type main.dsigddd_1·1 struct { ? int }$$!<binary segment>

Answer 3

我看到几个人抱怨“ for-loop”，类似“为什么i = 0; i < len; i++在这个时代必须说？”。我不同意，我喜欢for结构。如果愿意，可以使用长版本，但是惯用的Go是var a = []int{1, 2, 3}for i, v := range a {&nbsp; &nbsp; fmt.Println(i, v)}该for .. range构造在所有元素上循环并提供两个值-索引i和值v。range 也适用于地图和频道。不过，如果您不喜欢for任何形式，则可以在以下几行中定义each，map等等：type IntArr []int// 'each' takes a function argument.// The function must accept two ints, the index and value,// and will be called on each element in turn.func (a IntArr) each(fn func(index, value int)) {&nbsp; &nbsp; for i, v := range a {&nbsp; &nbsp; &nbsp; &nbsp; fn(i, v)&nbsp; &nbsp; }}func main() {&nbsp; &nbsp; var a = IntArr([]int{2, 0, 0, 9}) // create int slice and cast to IntArr&nbsp; &nbsp; var fnPrint = func(i, v int) {&nbsp; &nbsp; &nbsp; &nbsp; fmt.Println(i, ":", v)&nbsp; &nbsp; } // create a function&nbsp; &nbsp; a.each(fnPrint) // call on each element}印刷0 : 21 : 02 : 03 : 9我开始非常喜欢Go :)