File: typeswitch2.go

package info (click to toggle)
golang-1.19 1.19.4-1
  • links: PTS, VCS
  • area: main
  • in suites: bookworm
  • size: 146,248 kB
  • sloc: asm: 117,015; ansic: 7,010; sh: 2,114; javascript: 1,119; perl: 1,099; python: 365; makefile: 109; cpp: 39; f90: 8; awk: 7; objc: 4
file content (37 lines) | stat: -rw-r--r-- 655 bytes parent folder | download | duplicates (25)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
// 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 ""
}