golang clone 代码
文件路径：/src/strings/clone.go
/ Copyright 2021 The Go Authors. All rights reserved.
/ Use of this source code is governed by a BSD-style
/ license that can be found in the LICENSE file.
package strings
import (
"unsafe"
)
/ Clone returns a fresh copy of s.
/ It guarantees to make a copy of s into a new allocation,
/ which can be important when retaining only a small substring
/ of a much larger string. Using Clone can help such programs
/ use less memory. Of course, since using Clone makes a copy,
/ overuse of Clone can make programs use more memory.
/ Clone should typically be used only rarely, and only when
/ profiling indicates that it is needed.
/ For strings of length zero the string "" will be returned
/ and no allocation is made.
func Clone(s string) string {
if len(s) == 0 {
return ""
}
b := make([]byte, len(s))
copy(b, s)
return *(*string)(unsafe.Pointer(&b))
}