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// errorcheck
// Copyright 2011 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 erroneous type switches are caught by the compiler.
// Issue 2700, among other things.
// Does not compile.
package main
import (
"io"
)
type I interface {
M()
}
func main() {
var x I
switch x.(type) {
case string: // ERROR "impossible"
println("FAIL")
}
// Issue 2700: if the case type is an interface, nothing is impossible
var r io.Reader
_, _ = r.(io.Writer)
switch r.(type) {
case io.Writer:
}
// Issue 2827.
switch _ := r.(type) { // ERROR "invalid variable name _|no new variables?"
}
}
func noninterface() {
var i int
switch i.(type) { // ERROR "cannot type switch on non-interface value|not an interface"
case string:
case int:
}
type S struct {
name string
}
var s S
switch s.(type) { // ERROR "cannot type switch on non-interface value|not an interface"
}
}
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