添加06.2.md和相关的例子与问题解答

eBook/examples/chapter_6/blank_identifier.go

@@ -0,0 +1,15 @@
+package main
+
+import "fmt"
+
+func main() {
+        var i1 int
+        var f1 float32
+    i1, _, f1 = ThreeValues()
+    fmt.Printf("The int: %d, the float: %f \n", i1, f1)
+}
+
+func ThreeValues() (int, int, float32) {
+    return 5, 6, 7.5
+}
+

eBook/examples/chapter_6/minmax.go

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+package main
+
+import "fmt"
+
+func main() {
+    var min, max int
+    min, max = MinMax(78, 65)
+    fmt.Printf("Minmium is: %d, Maximum is: %d\n", min, max)
+}
+
+func MinMax(a int, b int) (min int, max int) {
+        if a < b {
+            min = a
+            max = b
+        } else { // a = b or a < b
+            min = b
+            max = a
+        }
+        return
+}

eBook/examples/chapter_6/multiple_return.go

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+package main
+
+import "fmt"
+
+var num int = 10
+var numx2, numx3 int
+
+func main() {
+    numx2, numx3 = getX2AndX3(num)
+    PrintValues()
+    numx2, numx3 = getX2AndX3_2(num)
+    PrintValues()
+}
+
+func PrintValues() {
+    fmt.Printf("num = %d, 2x num = %d, 3x num = %d\n", num, numx2, numx3)
+}
+
+func getX2AndX3(input int) (int, int) {
+    return 2 * input, 3 * input
+}
+
+func getX2AndX3_2(input int) (x2 int, x3 int) {
+    x2 = 2 * input
+    x3 = 3 * input
+    // return x2, x3
+        return
+}

eBook/examples/chapter_6/side_effect.go

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+package main
+
+import (
+    "fmt"
+)
+
+// this function changes reply:
+func Multiply(a, b int, reply *int) {
+    *reply = a * b
+}
+
+func main() {
+    n := 0
+    reply := &n
+    Multiply(10, 5, reply)
+    fmt.Println("Multiply:", *reply) // Multiply: 50
+}

eBook/examples/chapter_6/simple_function.go

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+package main
+
+import "fmt"
+
+func main() {
+    fmt.Printf("Multiply 2 * 5 * 6 = %d\n", MultiPly3Nums(2, 5, 6))
+    // var i1 int = MultiPly3Nums(2, 5, 6)
+    // fmt.Printf("MultiPly 2 * 5 * 6 = %d\n", i1)
+}
+
+func MultiPly3Nums(a int, b int, c int) int {
+    // var product int = a * b * c
+        // return product
+        return a * b * c
+}