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gopackage

Does it make sense to have two packages in the same directory?


I have a project that provides a library (exports some funcs) and also must provide a command-line interface (there must be an executable file).

Example of directory structure:

whatever.io/
    myproject/
        main.go
        myproject.go

The go compiler needs the package main and func main to start execution. My library needs the package myproject where I put stuff on it. This is what the go tool says when I am building another project that tries to import myproject:

main.go:5:2: found packages myproject (myproject.go) and main (main.go) in $GOPATH/src/whatever.io/myproject

So I believe there is no way to do it.

Should I move the library or the CLI to another package?


Solution

  • Just move your packages inside a new folder within the same directory of main.go. Remember to import the new package from the reference of the $GOPATH.

    Example:

    user@user:~/p/go/test/so-multipack$ ls -R
    .:
    a  main.go
    
    ./a:
    a.go
    user@user:~/p/go/test/so-multipack$ cat main.go 
    package main
    
    import (
        "../so-multipack/a"
    )
    func main(){
        a.Hello()
    }
    user@user:~/p/go/test/so-multipack$ cat a/a.go 
    package a
    import (
        "fmt"
    )
    func Hello(){
        fmt.Println("hello from a")
    }
    user@user:~/p/go/test/so-multipack$ go run main.go 
    hello from a
    user@user:~/p/go/test/so-multipack$ go build 
    user@user:~/p/go/test/so-multipack$ ls
    a  main.go  so-multipack
    user@user:~/p/go/test/so-multipack$ 
    

    Useful link:

    go build vs go build file.go