| // run -gcflags=-G=3 |
| |
| // Copyright 2022 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 |
| |
| func eql[P comparable](x, y P) { |
| if x != y { |
| panic("not equal") |
| } |
| } |
| |
| func expectPanic(f func()) { |
| defer func() { |
| if recover() == nil { |
| panic("function succeeded unexpectedly") |
| } |
| }() |
| f() |
| } |
| |
| func main() { |
| eql[int](1, 1) |
| eql(1, 1) |
| |
| // all interfaces implement comparable |
| var x, y any = 2, 2 |
| eql[any](x, y) |
| eql(x, y) |
| |
| // but we may get runtime panics |
| x, y = 1, 2 // x != y |
| expectPanic(func() { eql(x, y) }) |
| |
| x, y = main, main // functions are not comparable |
| expectPanic(func() { eql(x, y) }) |
| } |
