Go - First Program

Minimal Program

1. Create a folder and module:

   mkdir hello-go && cd hello-go
   go mod init example.com/hello
   

2. Create main.go:

   package main
   import "fmt"
   func main(){
       fmt.Println("First Go Program")
   }
   

3. Run it:

   go run .
   # Expected output:
   # First Go Program
   

Run vs Build

• go run . compiles to a temp binary and runs it.
• go build creates a binary in the current directory.

Common errors

• go: no go files listed: you’re not in the folder with main.go or the file is named differently.
• package main missing: executable programs must use package main and define func main().

Practice

• Print your name and today’s date on separate lines.
• Change the message and rebuild with go build, then run the binary.

Try:

1. Modify the message; re-run quickly with go run ..
2. Build the binary and run it directly.