go - What is the purpose of the package declaration?

Question

Every Go file starts with package <something>.

As far as I understand - and this is probably where I am missing some information - there are only two possible values for <something>: The name of the directory it is in*, or main. If it is main, all other files in that directory can only have main, too. If it is something else, the project is inconsistent/violating convention.

Now if it is the name of the directory, it's redundant, because the same information is, well, in the name of the directory.

If it is main, it's kind of useless, because as far as I can see there is no way to tell go build to "please build all main packages".

^{* Because, in other words, one directory is one package.}

Answer 1

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