Re: Draft RFC: new pragma: C<use namespace>

On 13 Sep 2000, Piers Cawley wrote:

> Hildo Biersma <[email protected]> writes:
> 
> > Piers Cawley wrote:
> > I'd like to use shorthands for A::B::C's Foo and X::Y::Z's Bar at the
> > same time.
> 
> Well you can't. The patch that I pinched this RFC from is a lexically


	How about if we added a list, @NAMES, into which you could assign
namespace shortcuts, something like this:

package main;

        push @NAMES, ("A::B::C" => 'ABC', 
                      "X::Y::Z" => 'XYZ',
                      "StupidlyLongMathThingie" => "SLMT",
                      "Bar::Baz" => ""
                     );

	ABC::do_stuff();               # prints "ABC";
	XYZ::do_stuff();               # prints "XYZ"; 
	SLMT::do_stuff();              # prints "4";
	# do_stuff();	               # [1]


	sub do_stuff() { print "main"; }

package A::B::C;
	sub do_stuff() { print "ABC"; }

package X::Y::Z;
	sub do_stuff() { print "XYZ"; }

package StupidlyLongMathThingie;
	sub do_stuff() { print 2 + 2; }

package Bar::Baz;
	sub do_stuff() { print "barbaz"; }
__END__

	Whenever the interpreter saw a namespace usage, it would need to
check @NAMES in addition to checking the included modules list.  

	The problem comes when the user aliases two different namespaces
to the same alias (e.g., "Foobar" => "F", "Foxtrot" => "F")

	In this case, if the usage is unambiguous (e.g., F::do_foxtrot(),
and the Foobar module does not contain a sub by that name), then perl
should raise a warning but go ahead and execute.  If the usage is
ambiguous, this should be a fatal error.


				Dave