go 迭代string数组操作 go for string[]

package main
import (
"fmt"
)
func main() {
  subsCodes := []string{"aaaa", "vvvvv", "dddd", "eeeee", "gfgggg"}
  for _, s := range subsCodes {
    fmt.Println(s)
  }
}

(gdb) l main.main
import (
  "fmt"
)
func main() {
  s := "hello, world!"
  b := []byte(s)
  fmt.Println(s, b)
(gdb) b 11
Breakpoint 1 at 0x487cd9: file /export/home/machao/src/test/strbytes.go, line 11.
(gdb) r
Starting program: /export/home/machao/src/test/test1 
Breakpoint 1, main.main () at /export/home/machao/src/test/strbytes.go:11
  fmt.Println(s, b)
(gdb) info locals
s = {
str = 0x4b8ccf "hello, world!level 3 resetload64 failednil stackbaseout of memorys.allocCount=srmount errorstill in listtimer expiredtriggerRatio=unreachable: value method xadd64 failedxchg64 failed nmidlelocked= on "..., len = 13}
b = {array = 0xc4200140e0 "hello, world!", len = 13, cap = 16}
(gdb) ptype s
type = struct string {
 uint8 *str;
 int len;
}
(gdb) ptype b
type = struct []uint8 {
 uint8 *array;
 int len;
 int cap;
}

package main
import (
  "fmt"
  "strings"
  "unsafe"
)
func str2bytes(s string) []byte {
  x := (*[2]uintptr)(unsafe.Pointer(&s))
  h := [3]uintptr{x[0], x[1], x[1]}
  return *(*[]byte)(unsafe.Pointer(&h))
}
func bytes2str(b []byte) string {
  return *(*string)(unsafe.Pointer(&b))
}
func main() {
  s := strings.Repeat("abc", 3)
  b := str2bytes(s)
  s2 := bytes2str(b)
  fmt.Println(b, s2)
}

package main
import (
 "testing"
 "io/ioutil"
 "time"
 "fmt"
)
var s, _ = ioutil.ReadFile("mydata4vipday.720.datx")
func test() {
 b := string(s)
 _ = []byte(b)
}
func test2() {
 b := bytes2str(s)
 _ = str2bytes(b)
}
func BenchmarkTest(b *testing.B) {
 t1 := time.Now()
 for i := 0; i < b.N; i++ {
   test()
 }
 fmt.Println("test", time.Now().Sub(t1), b.N)
}
func BenchmarkTestBlock(b *testing.B) {
 t1 := time.Now()
 for i := 0; i < b.N; i++ {
   test2()
 }
 fmt.Println("test block", time.Now().Sub(t1), b.N)
}