How to run Golang programs

Why not use go run main.go? You should be thinking about it. I’m using go run main.go to run my Golang programs, and why I should not use it?

Well the explanation is quite simple!

Let’s create a file called main.go:

package main

import "fmt"

func main() {
    fmt.Println("Hello, World!")
}

Run it with go run main.go and we should have a message:

Hello, World!

That’s it.

But

We always have a but, right! If we have two files: the one with main.go and another with hello.go:

package main    

import "fmt"

func main() {
    run()
}

package main    

import "fmt"

func run() {
    fmt.Println("Hello, World!")
}

Trying to run go run main.go will throw an error. That’s because go run only runs the file with main.go in it.

To fix this, we need to use go run . after creating the go.mod file. Or we can use go run main.go hello.go to run the file with hello.go in it.

go mod init
go run .

Fix

To run this structure properly, we need to use go run . This means that we will run the main function that it’s in the current directory.

Summary

• Why not use go run main.go?
• But we always have a but, right!
• Fix

source

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