Fix (or rewrite) the implementation of the C</(?{...})/> closures.
+=head1 A re-entrant regexp engine
+
+This will allow the use of a regex from inside (?{ }), (??{ }) and
+(?(?{ })|) constructs.
+
=head1 pragmata
=head2 lexical pragmas
Make the peephole optimizer optional.
+=head2 You WANT *how* many
+
+Currently contexts are void, scalar and list. split has a special mechanism in
+place to pass in the number of return values wanted. It would be useful to
+have a general mechanism for this, backwards compatible and little speed hit.
+This would allow proposals such as short circuiting sort to be implemented
+as a module on CPAN.
+
=head2 lexical aliases
Allow lexical aliases (maybe via the syntax C<my \$alias = \$foo>.
The old perltodo notes "This has been done in places, but needs a thorough
code review. Also fchdir is available in some platforms."
-=head2 foreach reverse
-
-The old perltodo notes that we could optimise foreach to iterate in reverse.
-(instead of making a reversed copy on the stack)
-
=head1 Tests
=head2 Make Schwern poorer
=head2 Optimize away @_
-The old perltodo notes "Look at the "reification" code in C<av.c>"
+The old perltodo notes "Look at the "reification" code in C<av.c>".
=head2 switch ops
the dormant C<nswitch> and C<cswitch> ops in F<pp.c>; using these opcodes would
be much faster."
-** Attach/detach debugger from running program
+=head2 Attach/detach debugger from running program
The old perltodo notes "With C<gdb>, you can attach the debugger to a running
program if you pass the process ID. It would be good to do this with the Perl
debugger on a running Perl program, although I'm not sure how it would be done."
ssh and screen do this with named pipes in tmp. Maybe we can too.
+=head2 A decent benchmark
+
+perlbench seems impervious to any recent changes made to the perl core. It would
+be useful to have a reasonable general benchmarking suite that roughly
+represented what current perl programs do, and measurably reported whether
+tweaks to the core improve, degrade or don't really affect performance, to
+guide people attempting to optimise the guts of perl.
+
+=head2 readpipe(LIST)
+
+system() accepts a LIST syntax (and a PROGRAM LIST syntax) to avoid
+running a shell. readpipe() (the function behind qx//) could be similarly
+extended.