golang convlit 代码
文件路径：/test/convlit.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 that illegal assignments with both explicit and implicit conversions of literals are detected.
/ Does not compile.
package main
import "unsafe"
/ explicit conversion of constants
var x1 = string(1)
var x2 string = string(1)
var x3 = int(1.5) / ERROR "convert|truncate"
var x4 int = int(1.5) / ERROR "convert|truncate"
var x5 = "a" + string(1)
var x6 = int(1e100) / ERROR "overflow|cannot convert"
var x7 = float32(1e1000) / ERROR "overflow|cannot convert"
/ unsafe.Pointer can only convert to/from uintptr
var _ = string(unsafe.Pointer(uintptr(65))) / ERROR "convert|conversion"
var _ = float64(unsafe.Pointer(uintptr(65))) / ERROR "convert|conversion"
var _ = int(unsafe.Pointer(uintptr(65))) / ERROR "convert|conversion"
/ implicit conversions merit scrutiny
var s string
var bad1 string = 1 / ERROR "conver|incompatible|invalid|cannot"
var bad2 = s + 1 / ERROR "conver|incompatible|invalid|cannot"
var bad3 = s + 'a' / ERROR "conver|incompatible|invalid|cannot"
var bad4 = "a" + 1 / ERROR "literals|incompatible|convert|invalid"
var bad5 = "a" + 'a' / ERROR "literals|incompatible|convert|invalid"
var bad6 int = 1.5 / ERROR "convert|truncate"
var bad7 int = 1e100 / ERROR "overflow|truncated to int|truncated"
var bad8 float32 = 1e200 / ERROR "overflow"
/ but these implicit conversions are okay
var good1 string = "a"
var good2 int = 1.0
var good3 int = 1e9
var good4 float64 = 1e20
/ explicit conversion of string is okay
var _ = []rune("abc")
var _ = []byte("abc")
/ implicit is not
var _ []int = "abc" / ERROR "cannot use|incompatible|invalid|cannot convert"
var _ []byte = "abc" / ERROR "cannot use|incompatible|invalid|cannot convert"
/ named string is okay
type Tstring string
var ss Tstring = "abc"
var _ = []rune(ss)
var _ = []byte(ss)
/ implicit is still not
var _ []rune = ss / ERROR "cannot use|incompatible|invalid"
var _ []byte = ss / ERROR "cannot use|incompatible|invalid"
/ named slice is now ok
type Trune []rune
type Tbyte []byte
var _ = Trune("abc") / ok
var _ = Tbyte("abc") / ok
/ implicit is still not
var _ Trune = "abc" / ERROR "cannot use|incompatible|invalid|cannot convert"
var _ Tbyte = "abc" / ERROR "cannot use|incompatible|invalid|cannot convert"