Hash to emoji in go

emohex.go

var emap = getEmap()

// EmoHex returns the 8 bits emoji representation of a byte slice
func EmoHex(in []byte) string {
	if os.Getenv("EMOJI") != "true" {
		return fmt.Sprintf("%x", in)
	}

	res := ""
	for _, el := range in {
		res += html.UnescapeString("&#" + strconv.Itoa(emap[int(el)]) + ";")
	}
	return res
}

// EmoStr returns the 8 bits emoji representation of a string
func EmoStr(in string) string {
	if os.Getenv("EMOJI") != "true" {
		return in
	}

	data, err := hex.DecodeString(in)
	if err != nil {
		panic(err)
	}
	return EmoHex(data)
}

func getEmap() [256]int {
	var emap [256]int
	emoji := [][]int{
		{0x1F601, 0x1F64F},
		{0x1F680, 0x1F6C0},
		{0x1F600, 0x1F636},
		{0x1F681, 0x1F6C5},
	}
	count := 0

	// Fill the emap, we need at least 256 emoji
	for _, value := range emoji {
		for x := value[0]; x < value[1]; x++ {
			emap[count] = x
			count++
			if count >= 256 {
				break
			}
		}
	}
	return emap
}

main.go

/*
	https://play.golang.org/p/rrLG3_id9m9
*/

package main

import (
	"fmt"
	"html"
	"strconv"
	"crypto/sha256"
)

func main() {
	// Ranges taken from:
	// http://apps.timwhitlock.info/emoji/tables/unicode
	var emap [256]int
	emoji := [][]int{
		{0x1F601, 0x1F64F},
		{0x1F680, 0x1F6C0},
		{0x1F600, 0x1F636},
		{0x1F681, 0x1F6C5},
	}
	count := 0

	// Fill the emap, we need at least 256 emoji
	for _, value := range emoji {
		for x := value[0]; x < value[1]; x++ {
			emap[count] = x
			count++
			if count >= 256 {
				break
			}
		}
	}
	fmt.Printf("There is %d emojis\n", count)
	
	h := sha256.New()
	h.Write([]byte("ahello world\n"))
	fmt.Printf("%x\n", h.Sum(nil))
	
	printHex(h.Sum(nil), emap)
}

func printHex(in []byte, emap [256]int) {
	res := ""
	for _, el := range in {
		res += html.UnescapeString("&#" + strconv.Itoa(emap[int(el)]) + ";")
	}
	fmt.Printf("Res: %s\n", res)
}