Go 泛型：Map 實現

Map.go

package main

import "fmt"

func Map[T any](arr []T, fn func(T) T) []T {
	newArr := make([]T, len(arr))
	for i := 0; i < len(arr); i++ {
		newArr[i] = fn(arr[i])
	}
	return newArr
}

func main() {
	arr := []int{1, 2, 3, 4, 5}
	arr2 := Map(arr, func(x int) int { return x * 2 })
	fmt.Println(arr2) // [2 4 6 8 10]
}