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package main
import (
"fmt"
"net/http"
"net/http/httptest"
)
func main() {
assertInt()
assertNil()
assertValue()
}
func assertInt() {
defer func() {
r := recover()
fmt.Println(r)
}()
var v interface{} = 1
println(v.(string))
}
func assertNil() {
defer func() {
r := recover()
fmt.Println(r)
}()
var v interface{}
println(v.(string))
}
func assertValue() {
defer func() {
r := recover()
fmt.Println(r)
}()
var v http.ResponseWriter = httptest.NewRecorder()
println(v.(http.Pusher))
}
// Output:
// 22:10: interface conversion: interface {} is int, not string
// 32:10: interface conversion: interface {} is nil, not string
// 42:10: interface conversion: *httptest.ResponseRecorder is not http.Pusher: missing method Push
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