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=head1 TITLE
Fix C<$pkg::$var> precedence issues with parsing of C<::>
=head1 VERSION
Maintainer: Nathan Wiger <[EMAIL PROTECTED]>
Date: 14 Aug 2000
Last Modified: 15 Sep 2000
Mailing List: [EMAIL PROTECTED]
Number: 103
Version: 2
Status: Frozen
=head1 ABSTRACT
Currently, trying to dynamically assign to unnamed classes is very
difficult:
$pkg::$var = $val; # error
${pkg}::$var = $val; # nope
${$pkg::$var} = $val; # you wish
${${pkg}::$var} = $val; # sorry
${"${pkg}::$var"} = $val; # works, but bleeech :-)
The precedence and parsing of the :: operator should be fixed to allow
easy access to anonymous package operations.
=head1 NOTES ON FREEZE
The first part of this RFC, interpolated method calls, was superceded by
RFC 222: "Interpolation of method calls", by Michael Schwern.
=head1 DESCRIPTION
In a perfect world, these should work in Perl 6:
$var = 'RaiseError';
$DBI::$var = 1 ; # $DBI::RaiseError = 1
$pkg = 'Class';
$var = 'DEBUG';
${${pkg}::$var} = 1; # $Class::DEBUG = 1
$subpkg = 'Special';
$class = $pkg . '::' . $subpkg;
require $class; # require Class::Special
$mypkg = 'Some::Package::Name';
$ret = $mkpkg::do_stuff(@a); # is &{"${mypkg}::do_stuff"}(@a) now
Currently, the precedence of :: does not allow these operations. Some of
the above examples may still require additional braces, but they
shouldn't require the types of contortions currently needed.
=head1 IMPLEMENTATION
Unfortunately, I don't have the time to think this part up yet. :-( I
will gladly contribute to the precedence and parsing rules discussions
that will ensue in the future if this RFC is accepted.
=head1 REFERENCES
Programming Perl, 2ed, for the ${"${pkg}::$var"} syntax
RFC 222: Interpolation of method calls
