added some functional tests (690b7e59) · Commits · bsmrgo / playground

functional/functional.go

0 → 100644

+79 −0

Original line number	Diff line number	Diff line
		package functional

		// IsEven ...
		func IsEven(n int) bool {
		return (n % 2) == 0
		}

		// IsOdd ...
		func IsOdd(n int) bool {
		return !IsEven(n)
		}

		// AddN ...
		func AddN(n int) func(v int) int {
		return func(v int) int {
		return v + n
		}
		}

		// Add ...
		func Add(a, b int) int {
		return a + b
		}

		// Mul ...
		func Mul(a, b int) int {
		return a * b
		}

		// Map ...
		func Map(vi []int, t func(v int) int) []int {
		vo := make([]int, len(vi))

		for i := range vi {
		vo[i] = t(vi[i])
		}

		return vo
		}

		// IntSlice ...
		type IntSlice []int

		// Map ...
		func (vi IntSlice) Map(t func(v int) int) IntSlice {
		return Map(vi, t)
		}

		// Reduce ...
		func Reduce(vi IntSlice, b int, t func(a, b int) int) int {
		r := b
		for i := range vi {
		r = t(r, vi[i])
		}
		return r
		}

		// Reduce ...
		func (vi IntSlice) Reduce(b int, t func(a, b int) int) int {
		return Reduce(vi, b, t)
		}

		// Filter ...
		func Filter(vi []int, t func(v int) bool) IntSlice {
		vo := []int{}

		for _, v := range vi {
		if t(v) {
		vo = append(vo, v)
		}
		}

		return vo
		}

		// Filter ...
		func (vi IntSlice) Filter(t func(v int) bool) IntSlice {
		return Filter(vi, t)
		}

0 → 100644

+67 −0

Original line number	Diff line number	Diff line
		package functional

		import (
		"testing"
		)

		func TestIsX(t *testing.T) {
		for _, tv := range []struct {
		n int
		b bool
		}{
		{n: 0, b: true},
		{n: 1, b: false},
		{n: 2, b: true},
		{n: 13, b: false},
		{n: 100, b: true},
		} {
		if b := IsEven(tv.n); b != tv.b {
		t.Errorf("isEven(%d) is %t, expected %t", tv.n, b, tv.b)
		}
		if b := IsOdd(tv.n); b == tv.b {
		t.Errorf("isOdd(%d) is %t, expected %t", tv.n, b, !tv.b)
		}
		}
		}

		func TestConcurrency1(t *testing.T) {

		vi := IntSlice{0, 1, 2, 3, 4}
		vr := []int{5, 6, 7, 8, 9}
		vx := []int{5, 7, 9}

		add5 := AddN(5)

		vo := Map(vi, add5)

		for i := range vi {
		if vr[i] != vo[i] {
		t.Errorf("vo[%d] is %d, expected %d", i, vo[i], vr[i])
		}
		}

		s := Reduce(vo, 0, Add)

		if s != 35 {
		t.Errorf("Reduce(%v, 0, Add) is %d, expected 35", vo, s)
		}

		vf := Filter(vo, IsOdd)

		for i := range vf {
		if vx[i] != vf[i] {
		t.Errorf("vf[%d] is %d, expected %d", i, vf[i], vx[i])
		}
		}

		y := Reduce(vf, 1, Mul)

		if y != 315 {
		t.Errorf("Reduce(%v, 0, Add) is %d, expected 315", vf, y)
		}

		z := vi.Map(add5).Filter(IsOdd).Reduce(1, Mul)
		if z != 315 {
		t.Errorf("%v... is %d, expected 315", vi, z)
		}
		}