$ perl -le "sub f($$@@){warn qq{@_}} f(@ARGV,@ARGV,@ARGV); " 1 2 3 4 5
5 5 1 2 3 4 5 at -e line 1.

## simulate "require"
$ perl -le " eval q{sub f($$@@){warn qq{@_}}}; f(@ARGV,@ARGV,@ARGV); " 1 2 3 4 5
1 2 3 4 5 1 2 3 4 5 1 2 3 4 5 at (eval 1) line 1.

## forward/early/prototype declaration
$ perl -le " sub f($$@@); eval q{sub f($$@@){warn qq{@_}}}; f(@ARGV,@ARGV,@ARGV); " 1 2 3 4 5
5 5 1 2 3 4 5 at (eval 1) line 1.