followed by a possibly empty set of declarations of functions,
types, variables, and constants.
</p>

<pre class="ebnf">
SourceFile       = PackageClause ";" { ImportDecl ";" } { TopLevelDecl ";" } .
</pre>

<h3 id="Package_clause">Package clause</h3>

<p>
A package clause begins each source file and defines the package
to which the file belongs.
</p>