modernc.org/gc@v1.0.1-0.20240304020402-f0dba7c97c2b/testdata/errchk/test/switch7.go (about) 1 // errorcheck 2 3 // Copyright 2016 The Go Authors. All rights reserved. 4 // Use of this source code is governed by a BSD-style 5 // license that can be found in the LICENSE file. 6 7 // Verify that type switch statements with duplicate cases are detected 8 // by the compiler. 9 // Does not compile. 10 11 package main 12 13 import "fmt" 14 15 func f4(e interface{}) { 16 switch e.(type) { 17 case int: 18 case int: // ERROR "duplicate case int in type switch" 19 case int64: 20 case error: 21 case error: // ERROR "duplicate case error in type switch" 22 case fmt.Stringer: 23 case fmt.Stringer: // ERROR "duplicate case fmt.Stringer in type switch" 24 case struct { 25 i int "tag1" 26 }: 27 case struct { 28 i int "tag2" 29 }: 30 case struct { // ERROR "duplicate case struct { i int .tag1. } in type switch" 31 i int "tag1" 32 }: 33 } 34 } 35