=head1 DESCRIPTION
-This is a list of wishes for Perl. It is maintained by Nathan
-Torkington for the Perl porters. Send updates to
-I<perl5-porters@perl.org>. If you want to work on any of these
-projects, be sure to check the perl5-porters archives for past ideas,
-flames, and propaganda. This will save you time and also prevent you
-from implementing something that Larry has already vetoed. One set
-of archives may be found at:
+This is a list of wishes for Perl. The tasks we think are smaller or easier
+are listed first. Anyone is welcome to work on any of these, but it's a good
+idea to first contact I<perl5-porters@perl.org> to avoid duplication of
+effort. By all means contact a pumpking privately first if you prefer.
- http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/
-
-
-=head1 Infrastructure
-
-=head2 Mailing list archives
-
-Chaim suggests contacting egroup and asking them to archive the other
-perl.org mailing lists. Probably not advocacy, but definitely
-perl6-porters, etc.
-
-=head2 Bug tracking system
-
-Richard Foley I<richard@perl.org> is writing one. We looked at
-several, like gnats and the Debian system, but at the time we
-investigated them, none met our needs. Since then, Jitterbug has
-matured, and may be worth reinvestigation.
-
-The system we've developed will eventually be recipient of perlbug
-mail. New bugs are entered into a mysql database, and sent on to
-perl5-porters with the subject line rewritten to include a "ticket
-number" (unique ID for the new bug). If the incoming message already
-had a ticket number in the subject line, then the message is logged
-against that bug. There is a separate email interface (not forwarding
-to p5p) that permits porters to claim, categorize, and close tickets.
-
-The next desire is a web interface. It is hoped that code can be
-reused between the mail and the web interfaces.
-
-The current delay in implementation is caused by perl.org lockups.
-One suspect is the mail handling system, possibly going into loops.
-
-We're probably going to need a bugmaster, someone who will look at
-every new "bug" and kill those that we already know about, those
-that are not bugs at all, etc.
-
-=head2 Regression Tests
-
-The test suite for Perl serves two needs: ensuring features work, and
-ensuring old bugs have not been reintroduced. Both need work.
-
-Brent LaVelle (lavelle@metronet.com) has stepped forward to work on
-performance tests and improving the size of the test suite.
-
-=over 4
-
-=item Coverage
+Whilst patches to make the list shorter are most welcome, ideas to add to
+the list are also encouraged. Check the perl5-porters archives for past
+ideas, and any discussion about them. One set of archives may be found at:
-Do the tests that come with Perl exercise every line (or every block,
-or ...) of the Perl interpreter, and if not then how can we make them
-do so?
-
-=item Regression
+ http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/
-No bug fixes should be made without a corresponding testsuite addition.
-This needs a dedicated enforcer, as the current pumpking is either too
-lazy or too stupid or both and lets enforcement wander all over the
-map. :-)
+What can we offer you in return? Fame, fortune, and everlasting glory? Maybe
+not, but if your patch is incorporated, then we'll add your name to the
+F<AUTHORS> file, which ships in the official distribution. How many other
+programming languages offer you 1 line of immortality?
-=item __DIE__
+=head1 The roadmap to 5.10
-Tests that fail need to be of a form that can be readily mailed
-to perlbug and diagnosed with minimal back-and-forth's to determine
-which test failed, due to what cause, etc.
+The roadmap to 5.10 envisages feature based releases, as various items in this
+TODO are completed.
-=item suidperl
+=head2 Needed for a 5.9.4 release
-We need regression/sanity tests for suidperl
+=over
-=item The 25% slowdown from perl4 to perl5
+=item *
-This value may or may not be accurate, but it certainly is
-eye-catching. For some things perl5 is faster than perl4, but often
-the reliability and extensability have come at a cost of speed. The
-benchmark suite that Gisle released earlier has been hailed as both a
-fantastic solution and as a source of entirely meaningless figures.
-Do we need to test "real applications"? Can you do so? Anyone have
-machines to dedicate to the task? Identify the things that have grown
-slower, and see if there's a way to make them faster.
+Review assertions. Review syntax to combine assertions. Assertions could take
+advantage of the lexical pragmas work. L</What hooks would assertions need?>
=back
-=head1 Configure
-
-Andy Dougherty maintain(ed|s) a list of "todo" items for the configure
-that comes with Perl. See Porting/pumpkin.pod in the latest
-source release.
-
-=head2 Install HTML
-
-Have "make install" give you the option to install HTML as well. This
-would be part of Configure. Andy Wardley (certified Perl studmuffin)
-will look into the current problems of HTML installation--is
-'installhtml' preventing this from happening cleanly, or is pod2html
-the problem? If the latter, Brad Appleton's pod work may fix the
-problem for free.
-
-=head1 Perl Language
-
-=head2 our ($var)
-
-Declare global variables (lexically or otherwise).
-
-=head2 64-bit Perl
-
-Verify complete 64 bit support so that the value of sysseek, or C<-s>, or
-stat(), or tell can fit into a perl number without losing precision.
-Work with the perl-64bit mailing list on perl.org.
-
-=head2 Prototypes
-
-=over 4
+=head2 Needed for a 5.9.5 release
-=item Named prototypes
+=over
-Add proper named prototypes that actually work usefully.
+=item *
+Implement L</_ prototype character>
-=item Indirect objects
-
-Fix prototype bug that forgets indirect objects.
-
-=item Method calls
-
-Prototypes for method calls.
-
-=item Context
-
-Return context prototype declarations.
-
-=item Scoped subs
-
-lexically-scoped subs, e.g. my sub
+=item *
+Implement L</state variables>
=back
-=head2 Built-in globbing
+=head2 Needed for a 5.9.6 release
-Currently the C<E<lt>*.cE<gt>> syntax calls the c shell. This causes
-problems on sites without csh, systems where fork() is expensive, and
-setuid environments. Decide between Glob::BSD and File::KGlob, move
-it into the core, and make Perl use it for globbing. Ben Holzman and
-Tye McQueen have claimed the pumpkin for this.
+Stabilisation. If all goes well, this will be the equivalent of a 5.10-beta.
-=head1 Perl Internals
+=head1 Tasks that only need Perl knowledge
-=head2 magic_setisa
+=head2 common test code for timed bail out
-C<magic_setisa> should be made to update %FIELDS [???]
+Write portable self destruct code for tests to stop them burning CPU in
+infinite loops. This needs to avoid using alarm, as some of the tests are
+testing alarm/sleep or timers.
-=head2 Garbage Collection
+=head2 POD -> HTML conversion in the core still sucks
-There was talk of a mark-and-sweep garbage collector at TPC2, but the
-(to users) unpredictable nature of its behaviour put some off.
-Sarathy, I believe, did the work. Here's what he has to say:
+Which is crazy given just how simple POD purports to be, and how simple HTML
+can be. It's not actually I<as> simple as it sounds, particularly with the
+flexibility POD allows for C<=item>, but it would be good to improve the
+visual appeal of the HTML generated, and to avoid it having any validation
+errors. See also L</make HTML install work>, as the layout of installation tree
+is needed to improve the cross-linking.
-Yeah, I hope to implement it someday too. The points that were
-raised in TPC2 were all to do with calling DESTROY() methods, but
-I think we can accomodate that by extending bless() to stash
-extra information for objects so we track their lifetime accurately
-for those that want their DESTROY() to be predictable (this will be
-a speed hit, naturally, and will therefore be optional, naturally. :)
-
-[N.B. Don't even ask me about this now! When I have the time to
-write a cogent summary, I'll post it.]
+The addition of C<Pod::Simple> and its related modules may make this task
+easier to complete.
-=head2 Reliable signals
+=head2 Parallel testing
-Sarathy and Dan Sugalski are working on this. Chip posted a patch
-earlier, but it was not accepted into 5.005. The issue is tricky,
-because it has the potential to greatly slow down the core.
+The core regression test suite is getting ever more comprehensive, which has
+the side effect that it takes longer to run. This isn't so good. Investigate
+whether it would be feasible to give the harness script the B<option> of
+running sets of tests in parallel. This would be useful for tests in
+F<t/op/*.t> and F<t/uni/*.t> and maybe some sets of tests in F<lib/>.
-There are at least three things to consider:
+Questions to answer
=over 4
-=item Alternate runops() for signal despatch
+=item 1
-Sarathy and Dan are discussed this on perl5-porters.
+How does screen layout work when you're running more than one test?
-=item Figure out how to die() in delayed sighandler
+=item 2
-=item Add tests for Thread::Signal
+How does the caller of test specify how many tests to run in parallel?
-=item Automatic tests against CPAN
+=item 3
-Is there some way to automatically build all/most of CPAN with
-the new Perl and check that the modules there pass all the tests?
+How do setup/teardown tests identify themselves?
=back
-=head2 Interpolated regex performance bugs
-
- while (<>) {
- $found = 0;
- foreach $pat (@patterns) {
- $found++ if /$pat/o;
- }
- print if $found;
- }
-
-The qr// syntax added in 5.005 has solved this problem, but
-it needs more thorough documentation.
-
-=head2 Memory leaks from failed eval/regcomp
-
-The only known memory leaks in Perl are in failed code or regexp
-compilation. Fix this. Hugo Van Der Sanden will attempt this but
-won't have tuits until January 1999.
-
-=head2 Make XS easier to use
-
-There was interest in SWIG from porters, but nothing has happened
-lately.
-
-=head2 Make embedded Perl easier to use
+Pugs already does parallel testing - can their approach be re-used?
-This is probably difficult for the same reasons that "XS For Dummies"
-will be difficult.
+=head2 Make Schwern poorer
-=head2 Namespace cleanup
+We should have for everything. When all the core's modules are tested,
+Schwern has promised to donate to $500 to TPF. We may need volunteers to
+hold him upside down and shake vigorously in order to actually extract the
+cash.
- CPP-space: restrict CPP symbols exported from headers
- header-space: move into CORE/perl/
- API-space: begin list of things that constitute public api
- env-space: Configure should use PERL_CONFIG instead of CONFIG etc.
-
-=head2 MULTIPLICITY
-
-Complete work on safe recursive interpreters C<Perl-E<gt>new()>.
-Sarathy says that a reference implementation exists.
-
-=head2 MacPerl
-
-Chris Nandor and Matthias Neeracher are working on better integrating
-MacPerl into the Perl distribution.
-
-=head1 Documentation
-
-There's a lot of documentation that comes with Perl. The quantity of
-documentation makes it difficult for users to know which section of
-which manpage to read in order to solve their problem. Tom
-Christiansen has done much of the documentation work in the past.
-
-=head2 A clear division into tutorial and reference
-
-Some manpages (e.g., perltoot and perlreftut) clearly set out to
-educate the reader about a subject. Other manpages (e.g., perlsub)
-are references for which there is no tutorial, or are references with
-a slight tutorial bent. If things are either tutorial or reference,
-then the reader knows which manpage to read to learn about a subject,
-and which manpage to read to learn all about an aspect of that
-subject. Part of the solution to this is:
-
-=head2 Remove the artificial distinction between operators and functions
-
-History shows us that users, and often porters, aren't clear on the
-operator-function distinction. The present split in reference
-material between perlfunc and perlop hinders user navigation. Given
-that perlfunc is by far the larger of the two, move operator reference
-into perlfunc.
-
-=head2 More tutorials
-
-More documents of a tutorial nature could help. Here are some
-candidates:
-
-=over 4
+See F<t/lib/1_compile.t> for the 3 remaining modules that need tests.
-=item Regular expressions
+=head2 Improve the coverage of the core tests
-Robin Berjon (r.berjon@ltconsulting.net) has volunteered.
+Use Devel::Cover to ascertain the core's test coverage, then add tests that
+are currently missing.
-=item I/O
+=head2 test B
-Mark-Jason Dominus (mjd@plover.com) has an outline for perliotut.
+A full test suite for the B module would be nice.
-=item pack/unpack
+=head2 A decent benchmark
-This is badly needed. There has been some discussion on the
-subject on perl5-porters.
+C<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. Gisle would welcome
+new tests for perlbench.
-=item Debugging
+=head2 fix tainting bugs
-Ronald Kimball (rjk@linguist.dartmouth.edu) has volunteered.
+Fix the bugs revealed by running the test suite with the C<-t> switch (via
+C<make test.taintwarn>).
-=head2 Include a search tool
+=head2 Dual life everything
-perldoc should be able to 'grep' fulltext indices of installed POD
-files. This would let people say:
+As part of the "dists" plan, anything that doesn't belong in the smallest perl
+distribution needs to be dual lifed. Anything else can be too. Figure out what
+changes would be needed to package that module and its tests up for CPAN, and
+do so. Test it with older perl releases, and fix the problems you find.
- perldoc -find printing numbers with commas
+=head2 Improving C<threads::shared>
-and get back the perlfaq entry on 'commify'.
+Investigate whether C<threads::shared> could share aggregates properly with
+only Perl level changes to shared.pm
-This solution, however, requires documentation to contain the keywords
-the user is searching for. Even when the users know what they're
-looking for, often they can't spell it.
+=head2 POSIX memory footprint
-=head2 Include a locate tool
+Ilya observed that use POSIX; eats memory like there's no tomorrow, and at
+various times worked to cut it down. There is probably still fat to cut out -
+for example POSIX passes Exporter some very memory hungry data structures.
-perldoc should be able to help people find the manpages on a
-particular high-level subject:
- perldoc -find web
-would tell them manpages, web pages, and books with material on web
-programming. Similarly C<perldoc -find databases>, C<perldoc -find
-references> and so on.
-We need something in the vicinity of:
- % perl -help random stuff
- No documentation for perl function `random stuff' found
- The following entry in perlfunc.pod matches /random/a:
- =item rand EXPR
-
- =item rand
-
- Returns a random fractional number greater than or equal to C<0> and less
- than the value of EXPR. (EXPR should be positive.) If EXPR is
- omitted, the value C<1> is used. Automatically calls C<srand()> unless
- C<srand()> has already been called. See also C<srand()>.
-
- (Note: If your rand function consistently returns numbers that are too
- large or too small, then your version of Perl was probably compiled
- with the wrong number of RANDBITS.)
- The following pod pages seem to have /stuff/a:
- perlfunc.pod (7 hits)
- perlfaq7.pod (6 hits)
- perlmod.pod (4 hits)
- perlsyn.pod (3 hits)
- perlfaq8.pod (2 hits)
- perlipc.pod (2 hits)
- perl5004delta.pod (1 hit)
- perl5005delta.pod (1 hit)
- perlcall.pod (1 hit)
- perldelta.pod (1 hit)
- perlfaq3.pod (1 hit)
- perlfaq5.pod (1 hit)
- perlhist.pod (1 hit)
- perlref.pod (1 hit)
- perltoc.pod (1 hit)
- perltrap.pod (1 hit)
- Proceed to open perlfunc.pod? [y] n
- Do you want to speak perl interactively? [y] n
- Should I dial 911? [y] n
- Do you need psychiatric help? [y] y
- <PELIZA> Hi, what bothers you today?
- A Python programmer in the next cubby is driving me nuts!
- <PELIZA> Hmm, thats fixable. Just [rest censored]
-=head2 Separate function manpages by default
-Perl should install 'manpages' for every function/operator into the
-3pl or 3p manual section. By default. The splitman program in the
-Perl source distribution does the work of turning big perlfunc into
-little 3p pages.
+=head1 Tasks that need a little sysadmin-type knowledge
-=head2 Users can't find the manpages
+Or if you prefer, tasks that you would learn from, and broaden your skills
+base...
-Make C<perldoc> tell users what they need to add to their .login or
-.cshrc to set their MANPATH correctly.
+=head2 Relocatable perl
-=head2 Install ALL Documentation
+The C level patches needed to create a relocatable perl binary are done, as
+is the work on F<Config.pm>. All that's left to do is the C<Configure> tweaking
+to let people specify how they want to do the install.
-Make the standard documentation kit include the VMS, OS/2, Win32,
-Threads, etc information. installperl and pod/Makefile should know
-enough to copy README.foo to perlfoo.pod before building everything,
-when appropriate.
+=head2 make HTML install work
-=head2 Outstanding issues to be documented
-
-Tom has a list of 5.005_5* features or changes that require
-documentation.
-
-Create one document that coherently explains the delta between the
-last camel release and the current release. perldelta was supposed
-to be that, but no longer. The things in perldelta never seemed to
-get placed in the right places in the real manpages, either. This
-needs work.
-
-=head2 Adapt www.linuxhq.com for Perl
-
-This should help glorify documentation and get more people involved in
-perl development.
-
-=head2 Replace man with a perl program
-
-Can we reimplement man in Perl? Tom has a start. I believe some of
-the Linux systems distribute a manalike. Alternatively, build on
-perldoc to remove the unfeatures like "is slow" and "has no apropos".
-
-=head2 Unicode tutorial
-
-We could use more work on helping people understand Perl's new
-Unicode support that Larry has created.
-
-=head1 Modules
-
-=head2 Update the POSIX extension to conform with the POSIX 1003.1 Edition 2
-
-The current state of the POSIX extension is as of Edition 1, 1991,
-whereas the Edition 2 came out in 1996. ISO/IEC 9945:1-1996(E),
-ANSI/IEEE Std 1003.1, 1996 Edition. ISBN 1-55937-573-6. The updates
-were legion: threads, IPC, and real time extensions.
-
-=head2 Module versions
-
-Automate the checking of versions in the standard distribution so
-it's easy for a pumpking to check whether CPAN has a newer version
-that we should be including?
-
-=head2 New modules
-
-Which modules should be added to the standard distribution? This ties
-in with the SDK discussed on the perl-sdk list at perl.org.
-
-=head2 Profiler
-
-Make the profiler (Devel::DProf) part of the standard release, and
-document it well.
-
-=head2 Tie Modules
+There is an C<installhtml> target in the Makefile. It's marked as
+"experimental". It would be good to get this tested, make it work reliably, and
+remove the "experimental" tag. This would include
=over 4
-=item VecArray
+=item 1
-Implement array using vec(). Nathan Torkington has working code to
-do this.
+Checking that cross linking between various parts of the documentation works.
+In particular that links work between the modules (files with POD in F<lib/>)
+and the core documentation (files in F<pod/>)
-=item SubstrArray
+=item 2
-Implement array using substr()
+Work out how to split C<perlfunc> into chunks, preferably one per function
+group, preferably with general case code that could be used elsewhere.
+Challenges here are correctly identifying the groups of functions that go
+together, and making the right named external cross-links point to the right
+page. Things to be aware of are C<-X>, groups such as C<getpwnam> to
+C<endservent>, two or more C<=items> giving the different parameter lists, such
+as
-=item VirtualArray
-
-Implement array using a file
-
-=item ShiftSplice
+ =item substr EXPR,OFFSET,LENGTH,REPLACEMENT
+
+ =item substr EXPR,OFFSET,LENGTH
+
+ =item substr EXPR,OFFSET
-Defines shift et al in terms of splice method
+and different parameter lists having different meanings. (eg C<select>)
=back
-=head2 Procedural options
-
-Support procedural interfaces for the common cases of Perl's
-gratuitously OOO modules. Tom objects to "use IO::File" reading many
-thousands of lines of code.
-
-=head2 RPC
-
-Write a module for transparent, portable remote procedure calls. (Not
-core). This touches on the CORBA and ILU work.
-
-=head2 y2k localtime/gmtime
-
-Write a module, Y2k::Catch, which overloads localtime and gmtime's
-returned year value and catches "bad" attempts to use it.
-
-=head2 Export File::Find variables
-
-Make File::Find export C<$name> etc manually, at least if asked to.
-
-=head2 Ioctl
-
-Finish a proper Ioctl module.
-
-=head2 Debugger attach/detach
-
-Permit a user to debug an already-running program.
-
-=head2 Regular Expression debugger
-
-Create a visual profiler/debugger tool that stepped you through the
-execution of a regular expression point by point. Ilya has a module
-to color-code and display regular expression parses and executions.
-There's something at http://tkworld.org/ that might be a good start,
-it's a Tk/Tcl RE wizard, that builds regexen of many flavours.
+=head2 compressed man pages
-=head2 Alternative RE Syntax
+Be able to install them. This would probably need a configure test to see how
+the system does compressed man pages (same directory/different directory?
+same filename/different filename), as well as tweaking the F<installman> script
+to compress as necessary.
-Make an alternative regular expression syntax that is accessed through
-a module. For instance,
+=head2 Add a code coverage target to the Makefile
- use RE;
- $re = start_of_line()
- ->literal("1998/10/08")
- ->optional( whitespace() )
- ->literal("[")
- ->remember( many( or( "-", digit() ) ) );
+Make it easy for anyone to run Devel::Cover on the core's tests. The steps
+to do this manually are roughly
- if (/$re/) {
- print "time is $1\n";
- }
-
-Newbies to regular expressions typically only use a subset of the full
-language. Perhaps you wouldn't have to implement the full feature set.
-
-=head2 Bundled modules
-
-Nicholas Clark (nick@flirble.org) had a patch for storing modules in
-zipped format. This needs exploring and concluding.
-
-=head2 Expect
-
-Adopt IO::Tty, make it as portable as Don Libes' "expect" (can we link
-against expect code?), and perfect a Perl version of expect. IO::Tty
-and expect could then be distributed as part of the core distribution,
-replacing Comm.pl and other hacks.
-
-=head2 GUI::Native
-
-A simple-to-use interface to native graphical abilities would
-be welcomed. Oh, Perl's access Tk is nice enough, and reasonably
-portable, but it's not particularly as fast as one would like.
-Simple access to the mouse's cut buffer or mouse-presses shouldn't
-required loading a few terabytes of Tk code.
-
-=head2 Update semibroken auxiliary tools; h2ph, a2p, etc.
-
-Kurt Starsinic is working on h2ph. mjd has fixed bugs in a2p in the
-past. a2p apparently doesn't work on nawk and gawk extensions.
-Graham Barr has an Include module that does h2ph work at runtime.
-
-=head2 POD Converters
-
-Brad's PodParser code needs to become part of the core, and the Pod::*
-and pod2* programs rewritten to use this standard parser. Currently
-the converters take different options, some behave in different
-fashions, and some are more picky than others in terms of the POD
-files they accept.
-
-=head2 pod2html
-
-A short-term fix: pod2html generates absolute HTML links. Make it
-generate relative links.
-
-=head2 Podchecker
-
-Something like lint for Pod would be good. Something that catches
-common errors as well as gross ones. Brad Appleton is putting
-together something as part of his PodParser work.
-
-=head1 Tom's Wishes
-
-=head2 Webperl
-
-Design a webperl environment that's as tightly integrated and as
-easy-to-use as Perl's current command-line environment.
-
-=head2 Mobile agents
-
-More work on a safe and secure execution environment for mobile
-agents would be neat; the Safe.pm module is a start, but there's a
-still a lot to be done in that area. Adopt Penguin?
-
-=head2 POSIX on non-POSIX
-
-Standard programming constructs for non-POSIX systems would help a
-lot of programmers stuck on primitive, legacy systems. For example,
-Microsoft still hasn't made a usable POSIX interface on their clunky
-systems, which means that standard operations such as alarm() and
-fork(), both critical for sophisticated client-server programming,
-must both be kludged around.
-
-I'm unsure whether Tom means to emulate alarm( )and fork(), or merely
-to provide a document like perlport.pod to say which features are
-portable and which are not.
-
-=head2 Portable installations
+=over 4
-Figure out a portable semi-gelled installation, that is, one without
-full paths. Larry has said that he's thinking about this. Ilya
-pointed out that perllib_mangle() is good for this.
+=item *
-=head1 Win32 Stuff
+do a normal C<Configure>, but include Devel::Cover as a module to install
+(see F<INSTALL> for how to do this)
-=head2 Get PERL_OBJECT building under gcc
+=item *
-B<Part done>, according to Sarathy. It builds under egcs on win32,
-but doesn't run for occult reasons. If anyone knows the right
-breed of chicken to sacrifice, please speak up.
+ make perl
-=head2 Rename new headers to be consistent with the rest
+=item *
-=head2 Sort out the spawnvp() mess
+ cd t; HARNESS_PERL_SWITCHES=-MDevel::Cover ./perl -I../lib harness
-=head2 Work out DLL versioning
+=item *
-=head2 Get PERL_OBJECT building on non-win32
+Process the resulting Devel::Cover database
-=head2 Style-check
+=back
-=head1 Would be nice to have
+This just give you the coverage of the F<.pm>s. To also get the C level
+coverage you need to
=over 4
-=item C<pack "(stuff)*">
+=item *
-=item Contiguous bitfields in pack/unpack
+Additionally tell C<Configure> to use the appropriate C compiler flags for
+C<gcov>
-=item lexperl
+=item *
-=item Bundled perl preprocessor
+ make perl.gcov
-=item Use posix calls internally where possible
+(instead of C<make perl>)
-=item format BOTTOM
+=item *
-=item -i rename file only when successfully changed
+After running the tests run C<gcov> to generate all the F<.gcov> files.
+(Including down in the subdirectories of F<ext/>
-=item All ARGV input should act like <>
+=item *
-=item report HANDLE [formats].
+(From the top level perl directory) run C<gcov2perl> on all the C<.gcov> files
+to get their stats into the cover_db directory.
-=item support in perlmain to rerun debugger
+=item *
-=item lvalue functions
-
-Tuomas Lukka, on behalf of the PDL project, greatly desires this and
-Ilya has a patch for it (probably against an older version of Perl).
-Tuomas points out that what PDL really wants is lvalue I<methods>,
-not just subs.
+Then process the Devel::Cover database
=back
-=head1 Possible pragmas
+It would be good to add a single switch to C<Configure> to specify that you
+wanted to perform perl level coverage, and another to specify C level
+coverage, and have C<Configure> and the F<Makefile> do all the right things
+automatically.
-=head2 'less'
+=head2 Make Config.pm cope with differences between build and installed perl
-(use less memory, CPU)
+Quite often vendors ship a perl binary compiled with their (pay-for)
+compilers. People install a free compiler, such as gcc. To work out how to
+build extensions, Perl interrogates C<%Config>, so in this situation
+C<%Config> describes compilers that aren't there, and extension building
+fails. This forces people into choosing between re-compiling perl themselves
+using the compiler they have, or only using modules that the vendor ships.
-=head1 Optimizations
+It would be good to find a way teach C<Config.pm> about the installation setup,
+possibly involving probing at install time or later, so that the C<%Config> in
+a binary distribution better describes the installed machine, when the
+installed machine differs from the build machine in some significant way.
-=head2 constant function cache
+=head2 make parallel builds work
-=head2 foreach(reverse...)
+Currently parallel builds (such as C<make -j3>) don't work reliably. We believe
+that this is due to incomplete dependency specification in the F<Makefile>.
+It would be good if someone were able to track down the causes of these
+problems, so that parallel builds worked properly.
-=head2 Cache eval tree
+=head2 linker specification files
+
+Some platforms mandate that you provide a list of a shared library's external
+symbols to the linker, so the core already has the infrastructure in place to
+do this for generating shared perl libraries. My understanding is that the
+GNU toolchain can accept an optional linker specification file, and restrict
+visibility just to symbols declared in that file. It would be good to extend
+F<makedef.pl> to support this format, and to provide a means within
+C<Configure> to enable it. This would allow Unix users to test that the
+export list is correct, and to build a perl that does not pollute the global
+namespace with private symbols.
+
+
+
+
+=head1 Tasks that need a little C knowledge
+
+These tasks would need a little C knowledge, but don't need any specific
+background or experience with XS, or how the Perl interpreter works
-Unless lexical outer scope used (mark in &compiling?).
+=head2 Make it clear from -v if this is the exact official release
+
+Currently perl from C<p4>/C<rsync> ships with a F<patchlevel.h> file that
+usually defines one local patch, of the form "MAINT12345" or "RC1". The output
+of perl -v doesn't report that a perl isn't an official release, and this
+information can get lost in bugs reports. Because of this, the minor version
+isn't bumped up until RC time, to minimise the possibility of versions of perl
+escaping that believe themselves to be newer than they actually are.
+
+It would be useful to find an elegant way to have the "this is an interim
+maintenance release" or "this is a release candidate" in the terse -v output,
+and have it so that it's easy for the pumpking to remove this just as the
+release tarball is rolled up. This way the version pulled out of rsync would
+always say "I'm a development release" and it would be safe to bump the
+reported minor version as soon as a release ships, which would aid perl
+developers.
-=head2 rcatmaybe
+This task is really about thinking of an elegant way to arrange the C source
+such that it's trivial for the Pumpking to flag "this is an official release"
+when making a tarball, yet leave the default source saying "I'm not the
+official release".
-=head2 Shrink opcode tables
+=head2 Tidy up global variables
-Via multiple implementations selected in peep.
+There's a note in F<intrpvar.h>
-=head2 Cache hash value
+ /* These two variables are needed to preserve 5.8.x bincompat because
+ we can't change function prototypes of two exported functions.
+ Probably should be taken out of blead soon, and relevant prototypes
+ changed. */
-Not a win, according to Guido.
+So doing this, and removing any of the unused variables still present would
+be good.
-=head2 Optimize away @_ where possible
+=head2 Ordering of "global" variables.
-=head2 Optimize sort by { $a <=> $b }
+F<thrdvar.h> and F<intrpvarh> define the "global" variables that need to be
+per-thread under ithreads, where the variables are actually elements in a
+structure. As C dictates, the variables must be laid out in order of
+declaration. There is a comment
+C</* Important ones in the first cache line (if alignment is done right) */>
+which implies that at some point in the past the ordering was carefully chosen
+(at least in part). However, it's clear that the ordering is less than perfect,
+as currently there are things such as 7 C<bool>s in a row, then something
+typically requiring 4 byte alignment, and then an odd C<bool> later on.
+(C<bool>s are typically defined as C<char>s). So it would be good for someone
+to review the ordering of the variables, to see how much alignment padding can
+be removed.
-Greg Bacon added several more sort optimizations. These have
-made it into 5.005_55, thanks to Hans Mulder.
+=head2 bincompat functions
-=head2 Rewrite regexp parser for better integrated optimization
+There are lots of functions which are retained for binary compatibility.
+Clean these up. Move them to mathom.c, and don't compile for blead?
-The regexp parser was rewritten for 5.005. Ilya's the regexp guru.
+=head2 am I hot or not?
-=head1 Vague possibilities
+The idea of F<pp_hot.c> is that it contains the I<hot> ops, the ops that are
+most commonly used. The idea is that by grouping them, their object code will
+be adjacent in the executable, so they have a greater chance of already being
+in the CPU cache (or swapped in) due to being near another op already in use.
-=over 4
+Except that it's not clear if these really are the most commonly used ops. So
+anyone feeling like exercising their skill with coverage and profiling tools
+might want to determine what ops I<really> are the most commonly used. And in
+turn suggest evictions and promotions to achieve a better F<pp_hot.c>.
-=item ref function in list context
+=head2 emulate the per-thread memory pool on Unix
-This seems impossible to do without substantially breaking code.
+For Windows, ithreads allocates memory for each thread from a separate pool,
+which it discards at thread exit. It also checks that memory is free()d to
+the correct pool. Neither check is done on Unix, so code developed there won't
+be subject to such strictures, so can harbour bugs that only show up when the
+code reaches Windows.
-=item make tr/// return histogram in list context?
+It would be good to be able to optionally emulate the Window pool system on
+Unix, to let developers who only have access to Unix, or want to use
+Unix-specific debugging tools, check for these problems. To do this would
+involve figuring out how the C<PerlMem_*> macros wrap C<malloc()> access, and
+providing a layer that records/checks the identity of the thread making the
+call, and recording all the memory allocated by each thread via this API so
+that it can be summarily free()d at thread exit. One implementation idea
+would be to increase the size of allocation, and store the C<my_perl> pointer
+(to identify the thread) at the start, along with pointers to make a linked
+list of blocks for this thread. To avoid alignment problems it would be
+necessary to do something like
-=item Loop control on do{} et al
+ union memory_header_padded {
+ struct memory_header {
+ void *thread_id; /* For my_perl */
+ void *next; /* Pointer to next block for this thread */
+ } data;
+ long double padding; /* whatever type has maximal alignment constraint */
+ };
-=item Explicit switch statements
-Nobody has yet managed to come up with a switch syntax that would
-allow for mixed hash, constant, regexp checks. Submit implementation
-with syntax, please.
+although C<long double> might not be the only type to add to the padding
+union.
-=item compile to real threaded code
+=head2 reduce duplication in sv_setsv_flags
-=item structured types
+C<Perl_sv_setsv_flags> has a comment
+C</* There's a lot of redundancy below but we're going for speed here */>
-=item Modifiable $1 et al
+Whilst this was true 10 years ago, the growing disparity between RAM and CPU
+speeds mean that the trade offs have changed. In addition, the duplicate code
+adds to the maintenance burden. It would be good to see how much of the
+redundancy can be pruned, particular in the less common paths. (Profiling
+tools at the ready...). For example, why does the test for
+"Can't redefine active sort subroutine" need to occur in two places?
-The intent is for this to be a means of editing the matched portions of
-the target string.
-=back
-=head1 To Do Or Not To Do
-These are things that have been discussed in the past and roundly
-criticized for being of questionable value.
+=head1 Tasks that need a knowledge of XS
-=head2 Making my() work on "package" variables
+These tasks would need C knowledge, and roughly the level of knowledge of
+the perl API that comes from writing modules that use XS to interface to
+C.
-Being able to say my($Foo::Bar), something that sounds ludicrous and
-the 5.6 pumpking has mocked.
+=head2 IPv6
-=head2 "or" testing defined not truth
+Clean this up. Check everything in core works
-We tell people that C<||> can be used to give a default value to a
-variable:
+=head2 shrink C<GV>s, C<CV>s
- $children = shift || 5; # default is 5 children
+By removing unused elements and careful re-ordering, the structures for C<AV>s
+and C<HV>s have recently been shrunk considerably. It's probable that the same
+approach would find savings in C<GV>s and C<CV>s, if not all the other
+larger-than-C<PVMG> types.
-which is almost (but not):
+=head2 merge Perl_sv_2[inpu]v
- $children = shift;
- $children = 5 unless $children;
+There's a lot of code shared between C<Perl_sv_2iv_flags>,
+C<Perl_sv_2uv_flags>, C<Perl_sv_2nv>, and C<Perl_sv_2pv_flags>. It would be
+interesting to see if some of it can be merged into common shared static
+functions. In particular, C<Perl_sv_2uv_flags> started out as a cut&paste
+from C<Perl_sv_2iv_flags> around 5.005_50 time, and it may be possible to
+replace both with a single function that returns a value or union which is
+split out by the macros in F<sv.h>
-but if the first argument was given and is "0", then it will be
-considered false by C<||> and C<5> used instead. Really we want
-an C<||>-like operator that behaves like:
+=head2 UTF8 caching code
- $children = shift;
- $children = 5 unless defined $children;
+The string position/offset cache is not optional. It should be.
-Namely, a C<||> that tests defined-ness rather than truth. One was
-discussed, and a patch submitted, but the objections were many. While
-there were objections, many still feel the need. At least it was
-decided that C<??> is the best name for the operator.
+=head2 Implicit Latin 1 => Unicode translation
-=head2 "dynamic" lexicals
+Conversions from byte strings to UTF-8 currently map high bit characters
+to Unicode without translation (or, depending on how you look at it, by
+implicitly assuming that the byte strings are in Latin-1). As perl assumes
+the C locale by default, upgrading a string to UTF-8 may change the
+meaning of its contents regarding character classes, case mapping, etc.
+This should probably emit a warning (at least).
- my $x;
- sub foo {
- local $x;
- }
+This task is incremental - even a little bit of work on it will help.
-Localizing, as Tim Bunce points out, is a separate concept from
-whether the variable is global or lexical. Chip Salzenberg had
-an implementation once, but Larry thought it had potential to
-confuse.
+=head2 autovivification
-=head2 "class"-based, rather than package-based "lexicals"
+Make all autovivification consistent w.r.t LVALUE/RVALUE and strict/no strict;
-This is like what the Alias module provides, but the variables would
-be lexicals reserved by perl at compile-time, which really are indices
-pointing into the pseudo-hash object visible inside every method so
-declared.
+This task is incremental - even a little bit of work on it will help.
-=head1 Threading
+=head2 Unicode in Filenames
-=head2 Modules
+chdir, chmod, chown, chroot, exec, glob, link, lstat, mkdir, open,
+opendir, qx, readdir, readlink, rename, rmdir, stat, symlink, sysopen,
+system, truncate, unlink, utime, -X. All these could potentially accept
+Unicode filenames either as input or output (and in the case of system
+and qx Unicode in general, as input or output to/from the shell).
+Whether a filesystem - an operating system pair understands Unicode in
+filenames varies.
-Which of the standard modules are thread-safe? Which CPAN modules?
-How easy is it to fix those non-safe modules?
+Known combinations that have some level of understanding include
+Microsoft NTFS, Apple HFS+ (In Mac OS 9 and X) and Apple UFS (in Mac
+OS X), NFS v4 is rumored to be Unicode, and of course Plan 9. How to
+create Unicode filenames, what forms of Unicode are accepted and used
+(UCS-2, UTF-16, UTF-8), what (if any) is the normalization form used,
+and so on, varies. Finding the right level of interfacing to Perl
+requires some thought. Remember that an OS does not implicate a
+filesystem.
-=head2 Testing
+(The Windows -C command flag "wide API support" has been at least
+temporarily retired in 5.8.1, and the -C has been repurposed, see
+L<perlrun>.)
-Threading is still experimental. Every reproducible bug identifies
-something else for us to fix. Find and submit more of these problems.
+=head2 Unicode in %ENV
-=head2 $AUTOLOAD
+Currently the %ENV entries are always byte strings.
-=head2 exit/die
+=head2 use less 'memory'
-Consistent semantics for exit/die in threads.
+Investigate trade offs to switch out perl's choices on memory usage.
+Particularly perl should be able to give memory back.
-=head2 External threads
+This task is incremental - even a little bit of work on it will help.
-Better support for externally created threads.
+=head2 Re-implement C<:unique> in a way that is actually thread-safe
-=head2 Thread::Pool
+The old implementation made bad assumptions on several levels. A good 90%
+solution might be just to make C<:unique> work to share the string buffer
+of SvPVs. That way large constant strings can be shared between ithreads,
+such as the configuration information in F<Config>.
-=head2 thread-safety
+=head2 Make tainting consistent
-Spot-check globals like statcache and global GVs for thread-safety.
-"B<Part done>", says Sarathy.
+Tainting would be easier to use if it didn't take documented shortcuts and
+allow taint to "leak" everywhere within an expression.
-=head2 Per-thread GVs
+=head2 readpipe(LIST)
-According to Sarathy, this would make @_ be the same in threaded
-and non-threaded, as well as helping solve problems like filehandles
-(the same filehandle currently cannot be used in two threads).
+system() accepts a LIST syntax (and a PROGRAM LIST syntax) to avoid
+running a shell. readpipe() (the function behind qx//) could be similarly
+extended.
-=head1 Compiler
-=head2 Optimization
-The compiler's back-end code-generators for creating bytecode or
-compilable C code could use optimization work.
-=head2 Byteperl
-Figure out how and where byteperl will be built for the various
-platforms.
+=head1 Tasks that need a knowledge of the interpreter
-=head2 Precompiled modules
+These tasks would need C knowledge, and knowledge of how the interpreter works,
+or a willingness to learn.
-Save byte-compiled modules on disk.
+=head2 lexical pragmas
-=head2 Executables
+Document the new support for lexical pragmas in 5.9.3 and how %^H works.
+Maybe C<re>, C<encoding>, maybe other pragmas could be made lexical.
-Auto-produce executable.
+=head2 Attach/detach debugger from running program
-=head2 Typed lexicals
+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.
-Typed lexicals should affect B::CC::load_pad.
+=head2 Constant folding
-=head2 Win32
+The peephole optimiser should trap errors during constant folding, and give
+up on the folding, rather than bailing out at compile time. It is quite
+possible that the unfoldable constant is in unreachable code, eg something
+akin to C<$a = 0/0 if 0;>
-Workarounds to help Win32 dynamic loading.
+=head2 LVALUE functions for lists
-=head2 END blocks
+The old perltodo notes that lvalue functions don't work for list or hash
+slices. This would be good to fix.
-END blocks need saving in compiled output, now that STOP blocks
-are available.
+=head2 LVALUE functions in the debugger
-=head2 _AUTOLOAD
+The old perltodo notes that lvalue functions don't work in the debugger. This
+would be good to fix.
-_AUTOLOAD prodding.
+=head2 _ prototype character
-=head2 comppadlist
+Study the possibility of adding a new prototype character, C<_>, meaning
+"this argument defaults to $_".
-Fix comppadlist (names in comppad_name can have fake SvCUR
-from where newASSIGNOP steals the field).
+=head2 state variables
-=head2 Cached compilation
+C<my $foo if 0;> is deprecated, and should be replaced with
+C<state $x = "initial value\n";> the syntax from Perl 6.
-Can we install modules as bytecode?
+=head2 @INC source filter to Filter::Simple
-=head1 Recently Finished Tasks
+The second return value from a sub in @INC can be a source filter. This isn't
+documented. It should be changed to use Filter::Simple, tested and documented.
-=head2 Figure a way out of $^(capital letter)
+=head2 regexp optimiser optional
-Figure out a clean way to extend $^(capital letter) beyond
-the 26 alphabets. (${^WORD} maybe?)
+The regexp optimiser is not optional. It should configurable to be, to allow
+its performance to be measured, and its bugs to be easily demonstrated.
-Mark-Jason Dominus sent a patch which went into 5.005_56.
+=head2 UNITCHECK
-=head2 Filenames
+Introduce a new special block, UNITCHECK, which is run at the end of a
+compilation unit (module, file, eval(STRING) block). This will correspond to
+the Perl 6 CHECK. Perl 5's CHECK cannot be changed or removed because the
+O.pm/B.pm backend framework depends on it.
-Make filenames in the distribution and in the standard module set
-be 8.3 friendly where feasible. Good luck changing the standard
-modules, though. B<Done>.
+=head2 optional optimizer
-=head2 Proper tied array support
+Make the peephole optimizer optional. Currently it performs two tasks as
+it walks the optree - genuine peephole optimisations, and necessary fixups of
+ops. It would be good to find an efficient way to switch out the
+optimisations whilst keeping the fixups.
-This was B<done> in 5.005 by Nick Ing-Simmons.
+=head2 You WANT *how* many
-=head2 Foreign lines
+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.
-Perl should be more generous in accepting foreign line terminations.
-Mostly B<done> in 5.005.
+=head2 lexical aliases
-=head2 Namespace cleanup
+Allow lexical aliases (maybe via the syntax C<my \$alias = \$foo>.
- symbol-space: "pl_" prefix for all global vars
- "Perl_" prefix for all functions
+=head2 entersub XS vs Perl
- CPP-space: stop malloc()/free() pollution unless asked
+At the moment pp_entersub is huge, and has code to deal with entering both
+perl and XS subroutines. Subroutine implementations rarely change between
+perl and XS at run time, so investigate using 2 ops to enter subs (one for
+XS, one for perl) and swap between if a sub is redefined.
-=head2 Explain tool
+=head2 Self ties
-Given a piece of Perl code, say what it does. B::Deparse is doing
-this. B<Done>.
+self ties are currently illegal because they caused too many segfaults. Maybe
+the causes of these could be tracked down and self-ties on all types re-
+instated.
-=head2 ISA.pm
+=head2 Optimize away @_
-Rename and alter ISA.pm. B<Done>. It is now base.pm.
+The old perltodo notes "Look at the "reification" code in C<av.c>".
-=head2 Automate maintenance of most PERL_OBJECT code
+=head2 What hooks would assertions need?
-B<Done>, says Sarathy.
+Assertions are in the core, and work. However, assertions needed to be added
+as a core patch, rather than an XS module in ext, or a CPAN module, because
+the core has no hooks in the necessary places. It would be useful to
+investigate what hooks would need to be added to make it possible to provide
+the full assertion support from a CPAN module, so that we aren't constraining
+the imagination of future CPAN authors.
-=head2 -iprefix.
-Added in 5.004_70. B<Done>
-=head2 gettimeofday
-See Time::HiRes.
-=head2 reference to compiled regexp
+=head1 Big projects
-B<done> This is the qr// support in 5.005.
+Tasks that will get your name mentioned in the description of the "Highlights
+of 5.10"
-=head2 eval qw() at compile time
+=head2 make ithreads more robust
-qw() is presently compiled as a call to split. This means the split
-happens at runtime. Change this so qw() is compiled as a real list
-assignment. This also avoids surprises like:
+Generally make ithreads more robust. See also L</iCOW>
- $a = () = qw(What will $a hold?);
+This task is incremental - even a little bit of work on it will help, and
+will be greatly appreciated.
-B<Done>. Tom Hughes submitted a patch that went into 5.005_55.
+=head2 iCOW
-=head2 autocroak?
+Sarathy and Arthur have a proposal for an improved Copy On Write which
+specifically will be able to COW new ithreads. If this can be implemented
+it would be a good thing.
-B<Done>. This is the Fatal.pm module, so any builtin that that does
-not return success automatically die()s. If you're feeling brave, tie
-this in with the unified exceptions scheme.
+=head2 (?{...}) closures in regexps
-=head2 Status variable
+Fix (or rewrite) the implementation of the C</(?{...})/> closures.
-$^C to track compiler/checker status. B<Done> in 5.005_54.
+=head2 A re-entrant regexp engine
-=cut
+This will allow the use of a regex from inside (?{ }), (??{ }) and
+(?(?{ })|) constructs.
projects / p5sagit/p5-mst-13.2.git / blobdiff