如何编写Go代码

demo02/for-continue.go

@@ -1,19 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {
-	// for i := 1; i < 10; i++ {
-	// 	if i%2 == 0 {
-	// 		fmt.Printf(" 偶数-%d", i)
-	// 		continue
-	// 	}
-	// 	fmt.Printf(" %d", i)
-	// }
-
-	i := 0
-    for ;i <= 10; { // initialisation and post are omitted
-        fmt.Printf("%d ", i)
-        i += 2
-    }
-}

demo02/for-demo01.go

@@ -1,12 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {
-	for i := 1; i < 10; i++ {
-		if i>5 {
-			break
-		}
-		fmt.Printf(" %d", i)
-	}
-}

demo02/hello_wrold.go

@@ -1,7 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {
-    fmt.Println("Hello World")
-}

demo04/demo04-01.go

@@ -1,13 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {  
-    a := true
-    b := false
-    fmt.Println("a:", a, "b:", b)
-    c := a && b
-    fmt.Println("c:", c)
-    d := a || b
-    fmt.Println("d:", d)
-}

demo04/demo04-02.go

@@ -1,9 +0,0 @@
-package main
-
-import "fmt"
-
-func main() {  
-    var a int = 89
-    b := 95
-    fmt.Println("value of a is", a, "and b is", b)
-}

demo04/demo04-03.go

@@ -1,14 +0,0 @@
-package main
-
-import (  
-    "fmt"
-    "unsafe"
-)
-
-func main() {  
-    var a int = 89
-    b := 95
-    fmt.Println("value of a is", a, "and b is", b)
-    fmt.Printf("type of a is %T, size of a is %d", a, unsafe.Sizeof(a)) //type and size of a
-    fmt.Printf("\ntype of b is %T, size of b is %d", b, unsafe.Sizeof(b)) //type and size of b
-}

demo04/demo04-04.go

@@ -1,16 +0,0 @@
-package main
-
-import (  
-    "fmt"
-)
-
-func main() {  
-    a, b := 5.67, 8.97
-    fmt.Printf("type of a %T b %T\n", a, b)
-    sum := a + b
-    diff := a - b
-    fmt.Println("sum", sum, "diff", diff)
-
-    no1, no2 := 56, 89
-    fmt.Println("sum", no1+no2, "diff", no1-no2)
-}

demo04/demo04-05.go

@@ -1,15 +0,0 @@
-package main
-
-import (  
-    "fmt"
-)
-
-func main() {  
-    c1 := complex(5,7)
-    c2 := 8 + 27i
-    cadd := c1 + c2
-    fmt.Println("sum:",cadd)
-
-    cmul := c1 * c2
-    fmt.Println("mul :",cmul)
-}

demo04/demo04-06.go

@@ -1,12 +0,0 @@
-package main
-
-import (  
-    "fmt"
-)
-
-func main() {  
-    first := "Wan"
-    last := "ShaoBo"
-    name := first +" "+ last
-    fmt.Println("My name is",name)
-}

demo04/demo04-07.go

@@ -1,12 +0,0 @@
-package main
-
-import (  
-    "fmt"
-)
-
-func main() {  
-    i := 55      //int
-    j := 67.8    //float64
-    sum := i + j //不允许 int + float64
-    fmt.Println(sum)
-}

demo04/demo04-08.go

@@ -1,10 +0,0 @@
-package main
-
-import (  
-    "fmt"
-)
-
-func main() {  
-    var a = 5.9/8
-    fmt.Printf("a's type %T value %v",a, a)
-}

geometry/geometry.go

@@ -1,18 +0,0 @@
-//geometry.go
-package main 
-
-import (  
-    "fmt"
-    "golang-tutorial/geometry/rectangle" //importing custom package
-)
-
-func main() {  
-    var rectLen, rectWidth float64 = 6, 7
-    fmt.Println("Geometrical shape properties")
-        /*Area function of rectangle package used
-        */
-    fmt.Printf("area of rectangle %.2f\n", rectangle.Area(rectLen, rectWidth))
-        /*Diagonal function of rectangle package used
-        */
-    fmt.Printf("diagonal of the rectangle %.2f ",rectangle.Diagonal(rectLen, rectWidth))
-}

geometry/geometry_.go

@@ -1,9 +0,0 @@
-package main
-
-import (  
-    _"golang-tutorial/geometry/rectangle" 
-)
-
-func main() {
-
-}

geometry/geometry_init.go

@@ -1,31 +0,0 @@
-//geometry.go
-package main 
-
-import (  
-    "fmt"
-    "golang-tutorial/geometry/rectangle" //importing custom package
-    "log"
-)
-/*
- * 1. package variables
-*/
-var rectLen, rectWidth float64 = -6, 7 
-
-/*
-*2. init function to check if length and width are greater than zero
-*/
-func init() {  
-    println("main package initialized")
-    if rectLen < 0 {
-        log.Fatal("length is less than zero")
-    }
-    if rectWidth < 0 {
-        log.Fatal("width is less than zero")
-    }
-}
-
-func main() {  
-    fmt.Println("Geometrical shape properties")
-    fmt.Printf("area of rectangle %.2f\n", rectangle.Area(rectLen, rectWidth))
-    fmt.Printf("diagonal of the rectangle %.2f ",rectangle.Diagonal(rectLen, rectWidth))
-}

geometry/rectangle/rectprops.go

@@ -1,21 +0,0 @@
-package rectangle
-
-import "math"  
-import "fmt"
-
-/*
- * init function added
- */
- func init() {  
-    fmt.Println("rectangle package initialized")
-}
-
-func Area(len, wid float64) float64 {  
-    area := len * wid
-    return area
-}
-
-func Diagonal(len, wid float64) float64 {  
-    diagonal := math.Sqrt((len * len) + (wid * wid))
-    return diagonal
-}

main.go

@@ -1,7 +1,11 @@
 package main
 
-import "fmt"
+import (
+    "fmt"
+    "github.com/Tinywan/golang-tutorial/stringutil"
+)    
 
 func main() {
-    fmt.Println("Hello HI")
+    //fmt.Println("Hello golang-tutorial!")
+    fmt.Printf(stringutil.Reverse("!oG ,olleH"))
 }

stringutil/reverse.go

@@ -0,0 +1,11 @@
+// Package stringutil contains utility functions for working with strings.
+package stringutil
+
+// Reverse returns its argument string reversed rune-wise left to right.
+func Reverse(s string) string {
+	r := []rune(s)
+	for i, j := 0, len(r)-1; i < len(r)/2; i, j = i+1, j-1 {
+		r[i], r[j] = r[j], r[i]
+	}
+	return string(r)
+}