sketch for fast str to WCHAR conversion

main.go

// You can edit this code!
// Click here and start typing.
package main

import (
	"fmt"
	"sync/atomic"
)

// general purpose function that tries fast conversion into provided bufOut
// if bufOut too small or nil, it allocates a buffer
// returns a slice of the buffer with the result
func ToWcharBuf(s string, bufOut []uint16) []uint16 {
	// do the conversion
	return bufOut
}

var (
	reusableBufTaken int32
	reusableBuf      []uint16
)

func ToWcharReusableBuf(s string) ([]uint16, bool) {
	// grab the buffer if available
	// if 0 (not taken) swap with 1 (taken)
	// returns true if swapped i.e. was not taken and we did take it
	weTookIt := atomic.CompareAndSwapInt32(&reusableBufTaken, 0, 1)
	var buf []uint16
	if weTookIt {
		buf = reusableBuf
	}
	res := ToWcharBuf()
	return buf, weTookIt
}

func ReleaseReusableBuf(release bool) {
	if release {
		atomic.Store(&reuasableBufTaken, 0)
	}
}

func useBuf() {
	ws, release := ToWcharReusableBuf(s)
	// ... use ws
	ReleaseReusableBuf(release)
}

func main() {
	fmt.Println("Hello, 世界")
}