| // compile |
| |
| // Copyright 2020 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. |
| |
| // Issue 40859. |
| package main |
| |
| import ( |
| "fmt" |
| ) |
| |
| type Number interface { |
| type int, int8, int16, int32, int64, uint, uint8, uint16, uint32, uint64, uintptr, float32, float64 |
| } |
| |
| type MySlice []int |
| |
| type SC[E any] interface { |
| type []E |
| } |
| |
| func DoubleDefined[S SC[E], E Number](s S) S { |
| r := make(S, len(s)) |
| for i, v := range s { |
| r[i] = v + v |
| } |
| return r |
| } |
| |
| func main() { |
| // Expicit types work fine |
| fmt.Println(DoubleDefined[MySlice, int](MySlice{1})) |
| |
| // Constraint type inference does not work? |
| fmt.Println(DoubleDefined(MySlice{1})) |
| } |
