| // run -gcflags=-G=3 |
| |
| // 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" |
| |
| type Exp[Ty any] interface { |
| Eval() Ty |
| } |
| |
| type Lit[Ty any] Ty |
| |
| func (lit Lit[Ty]) Eval() Ty { return Ty(lit) } |
| func (lit Lit[Ty]) String() string { return fmt.Sprintf("(lit %v)", Ty(lit)) } |
| |
| type Eq[Ty any] struct { |
| a Exp[Ty] |
| b Exp[Ty] |
| } |
| |
| func (e Eq[Ty]) String() string { |
| return fmt.Sprintf("(eq %v %v)", e.a, e.b) |
| } |
| |
| var ( |
| e0 = Eq[int]{Lit[int](128), Lit[int](64)} |
| e1 = Eq[bool]{Lit[bool](true), Lit[bool](true)} |
| ) |
| |
| func main() { |
| fmt.Printf("%v\n", e0) |
| fmt.Printf("%v\n", e1) |
| } |
