slices

package main

import (
	"fmt"

	"github.com/foomo/go/slices"
)

func main() {
	result := slices.Filter([]int{1, 2, 3, 4, 5}, func(n int) bool {
		return n%2 == 0
	})
	fmt.Println(result)
}

Output:
[2 4]

package main

import (
	"fmt"

	"github.com/foomo/go/slices"
)

func main() {
	type item struct {
		name     string
		category string
	}

	items := []item{
		{"apple", "fruit"},
		{"carrot", "vegetable"},
		{"banana", "fruit"},
	}
	groups := slices.GroupBy(items, func(i item) string {
		return i.category
	})
	fmt.Println(len(groups))
	fmt.Println(len(groups["fruit"]))
	fmt.Println(len(groups["vegetable"]))
}

Output:
2
2
1

package main

import (
	"fmt"

	"github.com/foomo/go/slices"
)

func main() {
	result := slices.Map([]int{1, 2, 3}, func(n int) int {
		return n * 2
	})
	fmt.Println(result)
}

Output:
[2 4 6]