2.8. Scope of a Package DirectiveAll files start as if you had said package main;. Any package directive remains in effect until the next package directive, unless that package directive is inside a curly-braced scope. In that case, the prior package is remembered and restored when the scope ends. Here's an example: package Navigation; { # start scope block package main; # now in package main sub turn_towards_heading { # main::turn_towards_heading .. code here .. } } # end scope block # back to package Navigation sub turn_towards_port { # Navigation::turn_towards_port .. code here .. } The current package is lexically scoped, similar to the scope of my variables, narrowed to the innermost-enclosing brace pair or file in which the package is introduced. Most libraries have only one package declaration at the top of the file. Most programs leave the package at the default main package. However it's nice to know that you can temporarily have a different current package.[13]
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