golang const1 代码
文件路径：/test/const1.go
/ 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 overflow is detected when using numeric constants.
/ Does not compile.
package main
import "unsafe"
type I interface{}
const (
/ assume all types behave similarly to int8/uint8
Int8 int8 = 101
Minus1 int8 = -1
Uint8 uint8 = 102
Const = 103
Float32 float32 = 104.5
Float64 float64 = 105.5
ConstFloat = 106.5
Big float64 = 1e300
String = "abc"
Bool = true
)
var (
a1 = Int8 * 100 / ERROR "overflow|cannot convert"
a2 = Int8 * -1 / OK
a3 = Int8 * 1000 / ERROR "overflow|cannot convert"
a4 = Int8 * int8(1000) / ERROR "overflow|cannot convert"
a5 = int8(Int8 * 1000) / ERROR "overflow|cannot convert"
a6 = int8(Int8 * int8(1000)) / ERROR "overflow|cannot convert"
a7 = Int8 - 2*Int8 - 2*Int8 / ERROR "overflow|cannot convert"
a8 = Int8 * Const / 100 / ERROR "overflow|cannot convert"
a9 = Int8 * (Const / 100) / OK
b1 = Uint8 * Uint8 / ERROR "overflow|cannot convert"
b2 = Uint8 * -1 / ERROR "overflow|cannot convert"
b3 = Uint8 - Uint8 / OK
b4 = Uint8 - Uint8 - Uint8 / ERROR "overflow|cannot convert"
b5 = uint8(^0) / ERROR "overflow|cannot convert"
b5a = int64(^0) / OK
b6 = ^uint8(0) / OK
b6a = ^int64(0) / OK
b7 = uint8(Minus1) / ERROR "overflow|cannot convert"
b8 = uint8(int8(-1)) / ERROR "overflow|cannot convert"
b8a = uint8(-1) / ERROR "overflow|cannot convert"
b9 byte = (1 << 10) >> 8 / OK
b10 byte = (1 << 10) / ERROR "overflow|cannot convert"
b11 byte = (byte(1) << 10) >> 8 / ERROR "overflow|cannot convert"
b12 byte = 1000 / ERROR "overflow|cannot convert"
b13 byte = byte(1000) / ERROR "overflow|cannot convert"
b14 byte = byte(100) * byte(100) / ERROR "overflow|cannot convert"
b15 byte = byte(100) * 100 / ERROR "overflow|cannot convert"
b16 byte = byte(0) * 1000 / ERROR "overflow|cannot convert"
b16a byte = 0 * 1000 / OK
b17 byte = byte(0) * byte(1000) / ERROR "overflow|cannot convert"
b18 byte = Uint8 / 0 / ERROR "division by zero"
c1 float64 = Big
c2 float64 = Big * Big / ERROR "overflow|cannot convert"
c3 float64 = float64(Big) * Big / ERROR "overflow|cannot convert"
c4 = Big * Big / ERROR "overflow|cannot convert"
c5 = Big / 0 / ERROR "division by zero"
c6 = 1000 % 1e3 / ERROR "invalid operation|expected integer type"
)
func f(int)
func main() {
f(Int8) / ERROR "convert|wrong type|cannot"
f(Minus1) / ERROR "convert|wrong type|cannot"
f(Uint8) / ERROR "convert|wrong type|cannot"
f(Const) / OK
f(Float32) / ERROR "convert|wrong type|cannot"
f(Float64) / ERROR "convert|wrong type|cannot"
f(ConstFloat) / ERROR "truncate"
f(ConstFloat - 0.5) / OK
f(Big) / ERROR "convert|wrong type|cannot"
f(String) / ERROR "convert|wrong type|cannot|incompatible"
f(Bool) / ERROR "convert|wrong type|cannot|incompatible"
}
const ptr = nil / ERROR "const.*nil|not constant"
const _ = string([]byte(nil)) / ERROR "is not a? ?constant"
const _ = uintptr(unsafe.Pointer((*int)(nil))) / ERROR "is not a? ?constant"
const _ = unsafe.Pointer((*int)(nil)) / ERROR "cannot be nil|invalid constant type|is not a constant|not constant"
const _ = (*int)(nil) / ERROR "cannot be nil|invalid constant type|is not a constant|not constant"