Manual Pages for UNIX Darwin command on man perltodo

PERLTODO(1) Perl Programmers Reference Guide PERLTODO(1)

NAME

perltodo - Perl TO-DO List

DESCRIPTION

This is a list of wishes for Perl. Send updates to

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 imple-

menting something that Larry has already vetoed. One set of archives may be found at:

http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/

aasssseerrttiioonnss Clean up and finish support for assertions. See assertions. iiCCOOWW 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 imple-

mented it would be a good thing. ((??{{......}})) cclloossuurreess iinn rreeggeexxppss Fix (or rewrite) the implementation of the "/(?{...})/" closures.

AA rree-eennttrraanntt rreeggeexxpp eennggiinnee

This will allow the use of a regex from inside (?{ }), (??{ }) and (?(?{ })|) constructs. pprraaggmmaattaa lleexxiiccaall pprraaggmmaass Reimplement the mechanism of lexical pragmas to be more extensible. Fix current pragmas that don't work well (or at all) with lexical scopes or

in run-time eval(STRING) ("sort", "re", "encoding" for example). MJD

has a preliminary patch that implements this. uussee lleessss ''mmeemmoorryy'' Investigate trade offs to switch out perl's choices on memory usage. Particularly perl should be able to give memory back. pprroottoottyyppeess aanndd ffuunnccttiioonnss pprroottoottyyppee cchhaarraacctteerr Study the possibility of adding a new prototype character, "", meaning

"this argument defaults to $".

iinnlliinniinngg aauuttoollooaaddeedd ccoonnssttaannttss

Currently the optimiser can inline constants when expressed as subrou-

tines with prototype ($) that return a constant. Likewise, many pack-

ages wrapping C libraries export lots of constants as subroutines which are AUTOLOADed on demand. However, these have no prototypes, so can't be seen as constants by the optimiser. Some way of cheaply (low syntax, low memory overhead) to the perl compiler that a name is a constant

would be great, so that it knows to call the AUTOLOAD routine at com-

pile time, and then inline the constant. FFiinniisshh ooffff llvvaalluuee ffuunnccttiioonnss

The old perltodo notes "They don't work in the debugger, and they don't

work for list or hash slices." UUnniiccooddee aanndd UUTTFF88 IImmpplliicciitt LLaattiinn 11 ==>> UUnniiccooddee ttrraannssllaattiioonn

Conversions from byte strings to UTF-8 currently map high bit charac-

ters 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). UUTTFF88 ccaacchhiinngg ccooddee The string position/offset cache is not optional. It should be. UUnniiccooddee iinn FFiilleennaammeess 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. 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 cre-

ate 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.

(The Windows -C command flag "wide API support" has been at least tem-

porarily retired in 5.8.1, and the -C has been repurposed, see perl-

run.)

UUnniiccooddee iinn %%EENNVV

Currently the %ENV entries are always byte strings.

RReeggeexxppss rreeggeexxpp ooppttiimmiisseerr ooppttiioonnaall The regexp optimiser is not optional. It should configurable to be, to

allow its performance to be measured, and its bugs to be easily demon-

strated. ccoommmmoonn ssuuffffiicceess//pprreeffiicceess iinn rreeggeexxppss ((ttrriiee ooppttiimmiizzaattiioonn)) Currently, the user has to optimize "foo|far" and "foo|goo" into "f(?:oo|ar)" and "[fg]oo" by hand; this could be done automatically. PPOODD

PPOODD ->> HHTTMMLL ccoonnvveerrssiioonn ssttiillll ssuucckkss

Which is crazy given just how simple POD purports to be, and how simple HTML can be. MMiisscc mmeeddiiuumm ssiizzeedd pprroojjeeccttss UUNNIITTCCHHEECCKK Introduce a new special block, UNITCHECK, which is run at the end of a

compilation unit (module, file, eval(STRING) block). This will corre-

spond 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. ooppttiioonnaall ooppttiimmiizzeerr Make the peephole optimizer optional. YYoouu WWAANNTT **hhooww** mmaannyy

Currently contexts are void, scalar and list. split has a special mech-

anism 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 cir-

cuiting sort to be implemented as a module on CPAN. lleexxiiccaall aalliiaasseess

Allow lexical aliases (maybe via the syntax "my \$alias = \$foo".

nnoo 66 Make "no 6" and "no v6" work (opposite of "use 5.005", etc.). IIPPvv66 Clean this up. Check everything in core works eenntteerrssuubb XXSS vvss PPeerrll At the moment ppentersub is huge, and has code to deal with entering both perl and 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. @@IINNCC ssoouurrccee ffiilltteerr ttoo FFiilltteerr::::SSiimmppllee 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. bbiinnccoommppaatt ffuunnccttiioonnss

There are lots of functions which are retained for binary compatibil-

ity. Clean these up. Move them to mathom.c, and don't compile for blead? UUssee ffcchhoowwnn//ffcchhmmoodd iinntteerrnnaallllyy

The old perltodo notes "This has been done in places, but needs a thor-

ough code review. Also fchdir is available in some platforms." TTeessttss MMaakkee SScchhwweerrnn ppoooorreerr

Tests for everything, At which point Schwern coughs up $500 to TPF.

tteesstt BB A test suite for the B module would be nice. IImmpprroovvee tteessttss ffoorr CCoonnffiigg..ppmm Config.pm doesn't appear to be well tested. ccoommmmoonn tteesstt ccooddee ffoorr ttiimmeedd bbaaiilloouutt Write portable self destruct code for tests to stop them burning CPU in infinite loops. Needs to avoid using alarm, as some of the tests are testing alarm/sleep or timers. IInnssttaallllaattiioonn ccoommpprreesssseedd mmaann ppaaggeess Be able to install them MMaakkee CCoonnffiigg..ppmm ccooppee wwiitthh ddiiffffeerreenncceess bbeettwweeeenn bbuuiilldd aanndd iinnssttaalllleedd ppeerrll RReellooccaattaabbllee ppeerrll Make it possible to create a relocatable perl binary. Will need some collusion with Config.pm. We could use a syntax of ... for location of current binary? mmaakkee HHTTMMLL iinnssttaallll wwoorrkk

ppuutt ppaattcchhlleevveell iinn -vv

Currently perl from p4/rsync ships with a patchlevel.h file that usu-

ally 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 possibil-

ity 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 ver-

sion 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. IInnccrreemmeennttaall tthhiinnggss Some tasks that don't need to get done in one big hit. aauuttoovviivviiffiiccaattiioonn Make all autovivification consistent w.r.t LVALUE/RVALUE and strict/no strict; ffiixx ttaaiinnttiinngg bbuuggss

Fix the bugs revealed by running the test suite with the "-t" switch

(via "make test.taintwarn"). MMaakkee ttaaiinnttiinngg ccoonnssiisstteenntt Tainting would be easier to use if it didn't take documented shortcuts and allow taint to "leak" everywhere within an expression. DDuuaall lliiffee eevveerryytthhiinngg

As part of the "dists" plan, anything that doesn't belong in the small-

est perl distribution needs to be dual lifed. Anything else can be too. VVaagguuee tthhiinnggss Some more nebulous ideas tthhrreeaaddss Make threads more robust. PPOOSSIIXX mmeemmoorryy ffoooottpprriinntt 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. OOppttiimmiizzee aawwaayy @@

The old perltodo notes "Look at the "reification" code in "av.c"".

sswwiittcchh ooppss

The old perltodo notes "Although we have "Switch.pm" in core, Larry

points to the dormant "nswitch" and "cswitch" ops in pp.c; using these opcodes would be much faster." AAttttaacchh//ddeettaacchh ddeebbuuggggeerr ffrroomm rruunnnniinngg pprrooggrraamm

The old perltodo notes "With "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. AA ddeecceenntt bbeenncchhmmaarrkk 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. rreeaaddppiippee((LLIISSTT)) system() accepts a LIST syntax (and a PROGRAM LIST syntax) to avoid

running a shell. readpipe() (the function behind qx//) could be simi-

larly extended.

perl v5.8.6 2004-11-05 PERLTODO(1)