main.go

package test

import (
	"regexp"

	guuid "github.com/google/uuid"
	suuid "github.com/satori/go.uuid"
)

var re = regexp.MustCompile("^[a-fA-F0-9]{8}-[a-fA-F0-9]{4}-4[a-fA-F0-9]{3}-[8|9|aA|bB][a-fA-F0-9]{3}-[a-fA-F0-9]{12}$")

func Func1(u string) bool {
	return re.MatchString(u)
}

func Func2(u string) bool {
	_, err := guuid.Parse(u)
	return err == nil
}

func Func3(u string) bool {
	_, err := suuid.FromString(u)
	return err == nil
}

main_test.go

package test

import (
	"testing"
)

var u = "2f6f97f2-5f44-476d-bc0c-180b2eaa36ca"

func Test_Func1(t *testing.T) {
	if Func1(u) != true {
		t.Fatal()
	}
}

func Test_Func2(t *testing.T) {
	if Func2(u) != true {
		t.Fatal()
	}
}

func Test_Func3(t *testing.T) {
	if Func3(u) != true {
		t.Fatal()
	}
}

func Benchmark_Func1(b *testing.B) {
	for i := 0; i < b.N; i++ {
		Func1(u)
	}
}

func Benchmark_Func2(b *testing.B) {
	for i := 0; i < b.N; i++ {
		Func2(u)
	}
}

func Benchmark_Func3(b *testing.B) {
	for i := 0; i < b.N; i++ {
		Func3(u)
	}
}

out.txt

goos: darwin
goarch: amd64
Benchmark_Func1-4   	 3000000	       588 ns/op	       0 B/op	       0 allocs/op
Benchmark_Func2-4   	50000000	        32 ns/op	       0 B/op	       0 allocs/op
Benchmark_Func3-4   	20000000	       106 ns/op	      48 B/op	       1 allocs/op
PASS
ok  	_/private/tmp/t3	6.137s