| // errorcheck |
| |
| // Copyright 2009 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. |
| |
| // Verify that various erroneous type switches are caught by the compiler. |
| // Does not compile. |
| |
| package main |
| |
| import "io" |
| |
| func whatis(x interface{}) string { |
| switch x.(type) { |
| case int: |
| return "int" |
| case int: // ERROR "duplicate" |
| return "int8" |
| case io.Reader: |
| return "Reader1" |
| case io.Reader: // ERROR "duplicate" |
| return "Reader2" |
| case interface { |
| r() |
| w() |
| }: |
| return "rw" |
| case interface { // ERROR "duplicate" |
| w() |
| r() |
| }: |
| return "wr" |
| |
| } |
| return "" |
| } |