Concatenation

src/hello/utils.go

package utils

import (
    "strings"
)

var names []string

func init() {
    for i := 'a'; i < 'z'; i++ {
        names = append(names, string(i)) // i is rune not compatible with names []string
    }
}

func Concatenate() string {
    var s, sep string
    for i := 0; i < len(names); i++ {
        s += sep + names[i]
        sep = " "
    }
    return s
}

func ConcatenateString() string {
     return strings.Join(names, " ")
}

src/hello/utils_test.go

package utils

import "testing"

func BenchmarkConcatenate(b *testing.B) {
    for i := 0; i < b.N; i++ {
        Concatenate()
    }
}

func BenchmarkConcatenateString(b *testing.B) {
    for i := 0; i < b.N; i++ {
        ConcatenateString()
    }
}