Golang Generics examples

example_custom_constraints.go

package main

import (
	"fmt"
)

func main() {

	var a, b uint
	a = 1
	b = 10

	fmt.Println(max(a, b))

}

type numOrder interface {
	int | uint | int8 | int16 | int32
}

func max[T numOrder](x, y T) T {

	if x >= y {
		return x
	}

	return y
}

example_genereics_packag_constraints2.go

package main

import (
	"fmt"

	"golang.org/x/exp/constraints"
)

func main() {

	list := []int{1, 2, 3, 4}

	a := 10

	fmt.Println(Contains(a, list))

	list2 := []string{"a", "b", "c", "d"}

	y := "a"

	fmt.Println(Contains(y, list2))
}

func Contains[T constraints.Ordered](n T, list []T) bool {
	for _, i := range list {
		if n == i {
			return true
		}
	}
	return false
}

example_package_constraints.go

package main

import (
	"fmt"

	"golang.org/x/exp/constraints"
)

func main() {

	var a, b uint
	var i, j string
	a = 12
	b = 56
	i = "abc"
	j = "def"

	fmt.Println(Max(a, b))
	fmt.Println(Max(i, j))

}

func Max[T constraints.Ordered](x, y T) T {
	if x >= y {
		return x
	}
	return y
}