Errors and Warnings

When you write code, GoLand will sometimes underline things to warn you.

What the underlines mean

GoLand sends color-coded messages to help you.

• Red underline (Error): “This cannot run.” The syntax is wrong or the code does not make sense. Your program will not run until you fix it.
• Yellow underline (Warning): “It runs, but there is a better way.” You did not follow Go’s rules or recommended style.

Go’s special rule

Go is famous for clean code, so it has a unique rule.

“If you declare it and do not use it, that is not allowed!”

If you create a variable (x := 10) and never use it, GoLand shows a red underline and raises an error. It is basically yelling, “Do not create it if you will not use it!”

This strictness is why Go code stays clean and tidy.