Short, readable, recursive implementation of Mergesort in Golang using slices

mergesort.go

// Mergesort

package main

import "fmt"

func Push(front int, rest []int) []int {
	new := make([]int, len(rest)+1)
	copy(new[1:], rest)
	new[0] = front
	return new
}

func Merge(a, b []int) []int {
	if len(a) == 0 {
		return b
	}
	if len(b) == 0 {
		return a
	}
	if a[0] < b[0] {
		return Push(a[0], Merge(a[1:], b))
	} else {
		return Push(b[0], Merge(b[1:], a))
	}
}

func MergeSort(sRef *[]int) {
	s := (*sRef)
	if len(s) <= 1 {
		return
	}
	median := (0 + (len(s) - 1)) / 2
	left := s[0 : median+1]
	right := s[median+1:]
	MergeSort(&left)
	MergeSort(&right)
	*sRef = Merge(left, right)
}

func main() {

	// Uncomment to try out Merge function
	// myTestSlice := []int{2,11,14,25,108,206}
	// myTestSlice2 := []int{1,4,8,18,24,27,39,100}
	// fmt.Println(Merge(myTestSlice, myTestSlice2))

	mySlice := []int{4, 235, 16, 3, 18, 74, 55, 29, 7, 646, 100, 82, 14, 66, 441, 12, 2}
	MergeSort(&mySlice)
	fmt.Println(mySlice)
}