golang fact 代码
文件路径：/test/typeparam/fact.go
/ run
/ Copyright 2021 The Go Authors. All rights reserved.
/ Use of this source code is governed by a BSD-style
/ license that can be found in the LICENSE file.
package main
import "fmt"
func fact[T interface{ ~int | ~int64 | ~float64 }](n T) T {
if n == 1 {
return 1
}
return n * fact(n-1)
}
func main() {
const want = 120
if got := fact(5); got != want {
panic(fmt.Sprintf("got %d, want %d", got, want))
}
if got := fact[int64](5); got != want {
panic(fmt.Sprintf("got %d, want %d", got, want))
}
if got := fact(5.0); got != want {
panic(fmt.Sprintf("got %f, want %f", got, want))
}
}