update commit

Author: 刘建秋

EN/defer.md

@@ -0,0 +1,119 @@
+# defer usage
+
+### defer Default execution order
+
+The defer method is an in - and out-stack structure.
+` ` `
+package main
+
+import(
+		"fmt"
+)
+
+func main(){
+	defer func(){
+	fmt.Println("1")
+	} ()
+	defer func(){
+	fmt.Println("2")
+	} ()
+	defer func(){
+	fmt.Println("3")
+	} ()
+
+	fmt.Println("4")
+	fmt.Println("5")
+
+	return
+}
+
+// output
+// 4
+// 5
+// 3
+// 2
+// 1
+` ` `
+
+### defer Aborts execution
+
+The defer stack operation after return will not be ignored
+` ` `
+package main
+
+import(
+	"fmt"
+)
+
+func main(){
+	defer func(){
+	fmt.Println("1")
+	} ()
+	defer func(){
+	fmt.Println("2")
+	} ()
+
+	return
+
+	defer func(){
+	fmt.Println("3")
+	} ()
+	defer func(){
+	fmt.Println("4")
+	} ()
+}
+
+// output
+// 2
+// 1
+` ` `
+
+### defer
+
+** * Avoid using this type of operation as it is not recommended because it is not readable **
+* If the return value is not declared as a specific variable, defer will not change the return value variable
+
+` ` `
+package main
+
+import(
+	"fmt"
+)
+
+func main(){
+	da := testA()
+	fmt.Println(da)
+
+	db := testB()
+	fmt.Println(db)
+}
+
+// Function body: name return value
+func testA()(data string) {
+	data = "OLD"
+	defer func(){
+	data = "NEW"
+	} ()
+	return res
+}
+
+// Function body: non-name return value
+func testB()(string) {
+	data := "OLD"
+	defer func(){
+	data = "NEW"
+	} ()
+	return res
+}
+
+// output
+// NEW
+// OLD
+` ` `
+
+# # # defer summary
+
+* defer is used to **ensure** that a function call is performed later in a program's execution, usually for purposes of cleanup. defer is often used where e.g. ensure and finally would be used in other languages.
+
+* defer in Go is like the C++ destructor; the Go area of C++ "destructors" is for functions, not objects.
+The * defer is the structure statement ** added when the function executes. It is the default, not the specified structure statement.

zh_CN/defer.md

@@ -0,0 +1,119 @@
+# defer 用法
+
+### defer 默认执行顺序
+
+defer方法是先进后出的栈入栈出结构。
+```
+package main
+
+import(
+	"fmt"
+)
+
+func main(){
+	defer func(){
+		fmt.Println("1")
+	}()
+	defer func(){
+		fmt.Println("2")
+	}()
+	defer func(){
+		fmt.Println("3")
+	}()
+
+	fmt.Println("4")
+	fmt.Println("5")
+
+	return
+}
+
+// output
+// 4
+// 5
+// 3
+// 2
+// 1
+```
+
+### defer 中止执行
+
+return之后的defer栈操作都不会被忽略
+```
+package main
+
+import(
+	"fmt"
+)
+
+func main(){
+	defer func(){
+		fmt.Println("1")
+	}()
+	defer func(){
+		fmt.Println("2")
+	}()
+
+	return
+
+	defer func(){
+		fmt.Println("3")
+	}()
+    defer func(){
+		fmt.Println("4")
+	}()
+}
+
+// output
+// 2
+// 1
+```
+
+### defer修改返回值注意事项
+
+* **尽量避免使用此类操作，可读性不强不推荐**
+* 返回值如果是非声明具体变量，则defer不会修改返回值变量
+
+```
+package main
+
+import(
+	"fmt"
+)
+
+func main(){
+	da := testA()
+	fmt.Println(da)
+
+    db := testB()
+	fmt.Println(db)
+}
+
+// 函数体：命名式返回值
+func testA()(data string) {
+	data = "OLD"
+	defer func(){
+		data = "NEW"
+	}()
+	return res
+}
+
+// 函数体：非命名式返回值
+func testB()(string) {
+	data := "OLD"
+	defer func(){
+		data = "NEW"
+	}()
+	return res
+}
+
+// output
+// NEW
+// OLD
+```
+
+### defer 小结
+
+* defer用于确保函数调用在程序执行的后期执行，通常用于清理。Defer通常用于其他语言中使用的地方，例如ensure和finally。
+
+* Go语言中defer类似于C++中的析构函数，Go语言区域于C++“析构“中针对的的是函数，而不是对象。
+* defer是函数执行时**添加**的结构语句，为缺省项，不是指定的结构语句。

zh_CN/map.md

@@ -17,7 +17,7 @@ mp2 := make(map[int]*[]int)
 只遍历键KEY时，使用下面的形式,无须将值改为匿名变量形式，忽略值即可:  
 ```
 for key := range mapData {
-    //Code ...
+    // Code ...
 }
 ```