【问题】
折腾:
【记录】go语言中把代码移至独立的函数中:搞懂go语言中函数的写法
期间,用如下代码:
package main
import (
"fmt"
"runtime"
"path"
"strings"
)
// GetCurFilename
// Get current file name, without suffix
func GetCurFilename() string {
_, fulleFilename, line, _ := runtime.Caller(0)
//fmt.Println(fulleFilename)
//fmt.Println(line)
var filenameWithSuffix string
filenameWithSuffix = path.Base(fulleFilename)
//fmt.Println("filenameWithSuffix=", filenameWithSuffix)
var fileSuffix string
fileSuffix = path.Ext(filenameWithSuffix)
//fmt.Println("fileSuffix=", fileSuffix)
//filenameWithSuffix = "EmulateLoginBaidu"
//fileSuffix = ".go"
//filenameWithSuffix = "EmulateLoginBaidu.go.go.go"
//fileSuffix = ".go"
//filenameWithSuffix = "EmulateLoginBaidu.go.txt"
//fileSuffix = ".go"
var filenameOnly string
filenameOnly = strings.TrimSuffix(filenameWithSuffix, fileSuffix)
//fmt.Println("filenameOnly=", filenameOnly)
return filenameOnly
}
func main() {
fmt.Printf("this is EmulateLoginBaidu.go\n")
var filenameOnly string
filenameOnly = GetCurFilename()
fmt.Println("filenameOnly=", filenameOnly)
}运行,结果出错:
D:\tmp\tmp_dev_root\go\src\github.com\user\EmulateLoginBaidu>go run EmulateLoginBaidu.go .\EmulateLoginBaidu.go:17: line declared and not used |
如图:
即:
line declared and not used |
【解决过程】
1.然后后来才注意到,原来是:
_, fulleFilename, line, _ := runtime.Caller(0)
//fmt.Println(fulleFilename)
//fmt.Println(line)中的返回值line,后面没有用到,所以有此警告。
2.所以,去参考:
_, fulleFilename, line, _ := runtime.Caller(0)
的写法,推测是:
下划线_,表示忽略此返回值,所以去改为:
func GetCurFilename() string {
_, fulleFilename, _, _ := runtime.Caller(0)
//fmt.Println(fulleFilename)试试结果:
然后程序就正常执行了,没有了此警告了:
D:\tmp\tmp_dev_root\go\src\github.com\user\EmulateLoginBaidu>go run EmulateLoginBaidu.go this is EmulateLoginBaidu.go filenameOnly= EmulateLoginBaidu
如图:
【总结】
go代码中,如果有变量(赋值了)但是后期没有引用,就会出现:
| line declared and not used |
的警告(而导致程序无法编译过,无法运行)
转载请注明:在路上 » 【已解决】go语言运行出错:# command-line-arguments .\EmulateLoginBaidu.go:17: line declared and not used