If it looks like UTF-8 (either nl_langinfo or locale variables),
[p5sagit/p5-mst-13.2.git] / pod / perltodo.pod
CommitLineData
7711098a 1=head1 NAME
2
3perltodo - Perl TO-DO List
4
5=head1 DESCRIPTION
e50bb9a1 6
722d2a37 7This is a list of wishes for Perl. Send updates to
e50bb9a1 8I<perl5-porters@perl.org>. If you want to work on any of these
9projects, be sure to check the perl5-porters archives for past ideas,
10flames, and propaganda. This will save you time and also prevent you
11from implementing something that Larry has already vetoed. One set
12of archives may be found at:
13
14 http://www.xray.mpe.mpg.de/mailing-lists/perl5-porters/
15
722d2a37 16=head1 To do during 5.6.x
e50bb9a1 17
722d2a37 18=head2 Support for I/O disciplines
e50bb9a1 19
722d2a37 20C<perlio> provides this, but the interface could be a lot more
21straightforward.
e50bb9a1 22
4b3b956a 23=head2 Autoload bytes.pm
e50bb9a1 24
4b3b956a 25When the lexer sees, for instance, C<bytes::length>, it should
26automatically load the C<bytes> pragma.
27
28=head2 Make "\u{XXXX}" et al work
29
30Danger, Will Robinson! Discussing the semantics of C<"\x{F00}">,
31C<"\xF00"> and C<"\U{F00}"> on P5P I<will> lead to a long and boring
32flamewar.
e50bb9a1 33
c6287c21 34=head2 Create a char *sv_pvprintify(sv, STRLEN *lenp, UV flags)
0562c0e3 35
36For displaying PVs with control characters, embedded nulls, and Unicode.
37This would be useful for printing warnings, or data and regex dumping,
38not_a_number(), and so on.
39
f35392ae 40Requirements: should handle both byte and UTF8 strings. isPRINT()
41characters printed as-is, character less than 256 as \xHH, Unicode
0661e9a4 42characters as \x{HHH}. Don't assume ASCII-like, either, get somebody
43on EBCDIC to test the output.
f35392ae 44
45Possible options, controlled by the flags:
0661e9a4 46- whitespace (other than ' ' of isPRINT()) printed as-is
f35392ae 47- use isPRINT_LC() instead of isPRINT()
48- print control characters like this: "\cA"
49- print control characters like this: "^A"
0661e9a4 50- non-PRINTables printed as '.' instead of \xHH
51- use \OOO instead of \xHH
52- use the C/Perl-metacharacters like \n, \t
f35392ae 53- have a maximum length for the produced string (read it from *lenp)
54- append a "..." to the produced string if the maximum length is exceeded
0661e9a4 55- really fancy: print unicode characters as \N{...}
f35392ae 56
1626a787 57NOTE: pv_display(), pv_uni_display(), sv_uni_display() are already
58doing something like the above.
c5fc23ff 59
722d2a37 60=head2 Overloadable regex assertions
e50bb9a1 61
722d2a37 62This may or may not be possible with the current regular expression
63engine. The idea is that, for instance, C<\b> needs to be
64algorithmically computed if you're dealing with Thai text. Hence, the
65B<\b> assertion wants to be overloaded by a function.
e50bb9a1 66
776f8809 67=head2 Unicode
68
69=over 4
70
71=item *
e50bb9a1 72
f34dec15 73Allow for long form of the General Category Properties, e.g
74C<\p{IsOpenPunctuation}>, not just the abbreviated form, e.g.
75C<\p{IsPs}>.
76
77=item *
78
1ac13f9a 79Allow for the metaproperties: C<XID Start>, C<XID Continue>,
80C<NF*_NO>, C<NF*_MAYBE> (require the DerivedCoreProperties and
81DerviceNormalizationProperties files).
f34dec15 82
71d929cb 83There are also multiple value properties still unimplemented:
84C<Numeric Type>, C<East Asian Width>.
f34dec15 85
86=item *
87
722d2a37 88 Case Mappings? http://www.unicode.org/unicode/reports/tr21/
e50bb9a1 89
6f16a292 90lc(), uc(), lcfirst(), and ucfirst() work only for some of the
91simplest cases, where the mapping goes from a single Unicode character
92to another single Unicode character. See lib/unicore/SpecCase.txt
93(and CaseFold.txt).
ac1256e8 94
776f8809 95=item *
e50bb9a1 96
c6287c21 97They have some tricks Perl doesn't yet implement like character
98class subtraction.
e50bb9a1 99
722d2a37 100 http://www.unicode.org/unicode/reports/tr18/
e50bb9a1 101
776f8809 102=back
103
104See L<perlunicode/UNICODE REGULAR EXPRESSION SUPPORT LEVEL> for what's
f34dec15 105there and what's missing. Almost all of Levels 2 and 3 is missing,
106and as of 5.8.0 not even all of Level 1 is there.
776f8809 107
722d2a37 108=head2 use Thread for iThreads
e50bb9a1 109
722d2a37 110Artur Bergman's C<iThreads> module is a start on this, but needs to
111be more mature.
e50bb9a1 112
dd0afe54 113=head2 make perl_clone optionally clone ops
114
115So that pseudoforking, mod_perl, iThreads and nvi will work properly
116(but not as efficiently) until the regex engine is fixed to be threadsafe.
117
722d2a37 118=head2 Work out exit/die semantics for threads
e50bb9a1 119
722d2a37 120=head2 Typed lexicals for compiler
e50bb9a1 121
722d2a37 122=head2 Compiler workarounds for Win32
e50bb9a1 123
722d2a37 124=head2 AUTOLOADing in the compiler
e50bb9a1 125
722d2a37 126=head2 Fixing comppadlist when compiling
e50bb9a1 127
722d2a37 128=head2 Cleaning up exported namespace
e50bb9a1 129
722d2a37 130=head2 Complete signal handling
e50bb9a1 131
722d2a37 132Add C<PERL_ASYNC_CHECK> to opcodes which loop; replace C<sigsetjmp> with
133C<sigjmp>; check C<wait> for signal safety.
e50bb9a1 134
722d2a37 135=head2 Out-of-source builds
e50bb9a1 136
722d2a37 137This was done for 5.6.0, but needs reworking for 5.7.x
e50bb9a1 138
722d2a37 139=head2 POSIX realtime support
e50bb9a1 140
722d2a37 141POSIX 1003.1 1996 Edition support--realtime stuff: POSIX semaphores,
142message queues, shared memory, realtime clocks, timers, signals (the
143metaconfig units mostly already exist for these)
e50bb9a1 144
722d2a37 145=head2 UNIX98 support
e50bb9a1 146
722d2a37 147Reader-writer locks, realtime/asynchronous IO
e50bb9a1 148
722d2a37 149=head2 IPv6 Support
e50bb9a1 150
fe854a6f 151There are non-core modules, such as C<Socket6>, but these will need
722d2a37 152integrating when IPv6 actually starts to really happen. See RFC 2292
153and RFC 2553.
e50bb9a1 154
722d2a37 155=head2 Long double conversion
e50bb9a1 156
722d2a37 157Floating point formatting is still causing some weird test failures.
e50bb9a1 158
722d2a37 159=head2 Locales
e50bb9a1 160
722d2a37 161Locales and Unicode interact with each other in unpleasant ways.
162One possible solution would be to adopt/support ICU:
e50bb9a1 163
722d2a37 164 http://oss.software.ibm.com/developerworks/opensource/icu/project/
e50bb9a1 165
722d2a37 166=head2 Thread-safe regexes
e50bb9a1 167
722d2a37 168The regular expression engine is currently non-threadsafe.
e50bb9a1 169
722d2a37 170=head2 Arithmetic on non-Arabic numerals
e50bb9a1 171
722d2a37 172C<[1234567890]> aren't the only numerals any more.
e50bb9a1 173
722d2a37 174=head2 POSIX Unicode character classes
e50bb9a1 175
210b36aa 176(C<[=a=]> for equivalance classes, C<[.ch.]> for collation.)
722d2a37 177These are dependent on Unicode normalization and collation.
e50bb9a1 178
722d2a37 179=head2 Factoring out common suffices/prefices in regexps (trie optimization)
c47ff5f1 180
722d2a37 181Currently, the user has to optimize C<foo|far> and C<foo|goo> into
182C<f(?:oo|ar)> and C<[fg]oo> by hand; this could be done automatically.
e50bb9a1 183
722d2a37 184=head2 Security audit shipped utilities
e50bb9a1 185
722d2a37 186All the code we ship with Perl needs to be sensible about temporary file
187handling, locking, input validation, and so on.
e50bb9a1 188
c8d2171d 189=head2 Sort out the uid-setting mess
190
191Currently there are several problems with the setting of uids ($<, $>
192for the real and effective uids). Firstly, what exactly setuid() call
193gets invoked in which platform is simply a big mess that needs to be
194untangled. Secondly, the effects are apparently not standard across
195platforms, (if you first set $< and then $>, or vice versa, being
196uid==euid== zero, or just euid==zero, or as a normal user, what are
197the results?). The test suite not (usually) being run as root means
198that these things do not get much testing. Thirdly, there's quite
199often a third uid called saved uid, and Perl has no knowledge of that
200feature in any way. (If one has the saved uid of zero, one can get
201back any real and effective uids.) As an example, to change also the
202saved uid, one needs to set the real and effective uids B<twice>-- in
203most systems, that is: in HP-UX that doesn't seem to work.
204
722d2a37 205=head2 Custom opcodes
e50bb9a1 206
722d2a37 207Have a way to introduce user-defined opcodes without the subroutine call
208overhead of an XSUB; the user should be able to create PP code. Simon
209Cozens has some ideas on this.
e50bb9a1 210
722d2a37 211=head2 DLL Versioning
e50bb9a1 212
d1be9408 213Windows needs a way to know what version of an XS or C<libperl> DLL it's
722d2a37 214loading.
e50bb9a1 215
722d2a37 216=head2 Introduce @( and @)
e50bb9a1 217
722d2a37 218C<$(> may return "foo bar baz". Unfortunately, since groups can
219theoretically have spaces in their names, this could be one, two or
220three groups.
e50bb9a1 221
722d2a37 222=head2 Floating point handling
e50bb9a1 223
722d2a37 224C<NaN> and C<inf> support is particularly troublesome.
225(fp_classify(), fp_class(), fp_class_d(), class(), isinf(),
226isfinite(), finite(), isnormal(), unordered(), <ieeefp.h>,
227<fp_class.h> (there are metaconfig units for all these) (I think),
228fp_setmask(), fp_getmask(), fp_setround(), fp_getround()
229(no metaconfig units yet for these). Don't forget finitel(), fp_classl(),
230fp_class_l(), (yes, both do, unfortunately, exist), and unorderedl().)
e50bb9a1 231
210b36aa 232As of Perl 5.6.1, there is a Perl macro, Perl_isnan().
e50bb9a1 233
722d2a37 234=head2 IV/UV preservation
e50bb9a1 235
722d2a37 236Nicholas Clark has done a lot of work on this, but work is continuing.
237C<+>, C<-> and C<*> work, but guards need to be in place for C<%>, C</>,
238C<&>, C<oct>, C<hex> and C<pack>.
e50bb9a1 239
722d2a37 240=head2 Replace pod2html with something using Pod::Parser
83df6a1d 241
fe854a6f 242The CPAN module C<Marek::Pod::Html> may be a more suitable basis for a
722d2a37 243C<pod2html> convertor; the current one duplicates the functionality
244abstracted in C<Pod::Parser>, which makes updating the POD language
245difficult.
e50bb9a1 246
722d2a37 247=head2 Automate module testing on CPAN
e50bb9a1 248
722d2a37 249When a new Perl is being beta tested, porters have to manually grab
250their favourite CPAN modules and test them - this should be done
251automatically.
e50bb9a1 252
722d2a37 253=head2 sendmsg and recvmsg
83df6a1d 254
722d2a37 255We have all the other BSD socket functions but these. There are
256metaconfig units for these functions which can be added. To avoid these
257being new opcodes, a solution similar to the way C<sockatmark> was added
258would be preferable. (Autoload the C<IO::whatever> module.)
e50bb9a1 259
722d2a37 260=head2 Rewrite perlre documentation
e50bb9a1 261
722d2a37 262The new-style patterns need full documentation, and the whole document
263needs to be a lot clearer.
e50bb9a1 264
722d2a37 265=head2 Convert example code to IO::Handle filehandles
e50bb9a1 266
722d2a37 267=head2 Document Win32 choices
e50bb9a1 268
722d2a37 269=head2 Check new modules
e50bb9a1 270
722d2a37 271=head2 Make roffitall find pods and libs itself
e50bb9a1 272
722d2a37 273Simon Cozens has done some work on this but it needs a rethink.
e50bb9a1 274
722d2a37 275=head1 To do at some point
e50bb9a1 276
722d2a37 277These are ideas that have been regularly tossed around, that most
278people believe should be done maybe during 5.8.x
e50bb9a1 279
722d2a37 280=head2 Remove regular expression recursion
e50bb9a1 281
722d2a37 282Because the regular expression engine is recursive, badly designed
283expressions can lead to lots of recursion filling up the stack. Ilya
284claims that it is easy to convert the engine to being iterative, but
285this has still not yet been done. There may be a regular expression
286engine hit squad meeting at TPC5.
e50bb9a1 287
722d2a37 288=head2 Memory leaks after failed eval
e50bb9a1 289
722d2a37 290Perl will leak memory if you C<eval "hlagh hlagh hlagh hlagh">. This is
291partially because it attempts to build up an op tree for that code and
292doesn't properly free it. The same goes for non-syntactically-correct
293regular expressions. Hugo looked into this, but decided it needed a
294mark-and-sweep GC implementation.
e50bb9a1 295
722d2a37 296Alan notes that: The basic idea was to extend the parser token stack
297(C<YYSTYPE>) to include a type field so we knew what sort of thing each
210b36aa 298element of the stack was. The F<perly.c> code would then have to be
722d2a37 299postprocessed to record the type of each entry on the stack as it was
300created, and the parser patched so that it could unroll the stack
301properly on error.
e50bb9a1 302
722d2a37 303This is possible to do, but would be pretty messy to implement, as it
304would rely on even more sed hackery in F<perly.fixer>.
e50bb9a1 305
722d2a37 306=head2 bitfields in pack
e50bb9a1 307
722d2a37 308=head2 Cross compilation
e50bb9a1 309
722d2a37 310Make Perl buildable with a cross-compiler. This will play havoc with
da75cd15 311Configure, which needs to know how the target system will respond to
722d2a37 312its tests; maybe C<microperl> will be a good starting point here.
313(Indeed, Bart Schuller reports that he compiled up C<microperl> for
314the Agenda PDA and it works fine.) A really big spanner in the works
315is the bootstrapping build process of Perl: if the filesystem the
316target systems sees is not the same what the build host sees, various
317input, output, and (Perl) library files need to be copied back and forth.
e50bb9a1 318
f86a8bc5 319As of 5.8.0 Configure mostly works for cross-compilation
320(used successfully for iPAQ Linux), miniperl gets built,
321but then building DynaLoader (and other extensions) fails
322since MakeMaker knows nothing of cross-compilation.
323(See INSTALL/Cross-compilation for the state of things.)
324
722d2a37 325=head2 Perl preprocessor / macros
e50bb9a1 326
722d2a37 327Source filters help with this, but do not get us all the way. For
328instance, it should be possible to implement the C<??> operator somehow;
329source filters don't (quite) cut it.
e50bb9a1 330
722d2a37 331=head2 Perl lexer in Perl
a45bd81d 332
722d2a37 333Damian Conway is planning to work on this, but it hasn't happened yet.
e50bb9a1 334
722d2a37 335=head2 Using POSIX calls internally
e50bb9a1 336
210b36aa 337When faced with a BSD vs. SysV -style interface to some library or
722d2a37 338system function, perl's roots show in that it typically prefers the BSD
339interface (but falls back to the SysV one). One example is getpgrp().
340Other examples include C<memcpy> vs. C<bcopy>. There are others, mostly in
210b36aa 341F<pp_sys.c>.
e50bb9a1 342
722d2a37 343Mostly, this item is a suggestion for which way to start a journey into
344an C<#ifdef> forest. It is not primarily a suggestion to eliminate any of
345the C<#ifdef> forests.
e50bb9a1 346
722d2a37 347POSIX calls are perhaps more likely to be portable to unexpected
348architectures. They are also perhaps more likely to be actively
349maintained by a current vendor. They are also perhaps more likely to be
350available in thread-safe versions, if appropriate.
e50bb9a1 351
722d2a37 352=head2 -i rename file when changed
e50bb9a1 353
722d2a37 354It's only necessary to rename a file when inplace editing when the file
355has changed. Detecting a change is perhaps the difficult bit.
e50bb9a1 356
722d2a37 357=head2 All ARGV input should act like E<lt>E<gt>
e50bb9a1 358
2d84a16a 359eg C<read(ARGV, ...)> doesn't currently read across multiple files.
360
722d2a37 361=head2 Support for rerunning debugger
e50bb9a1 362
722d2a37 363There should be a way of restarting the debugger on demand.
e50bb9a1 364
c6287c21 365=head2 Test Suite for the Debugger
366
367The debugger is a complex piece of software and fixing something
368here may inadvertently break something else over there. To tame
369this chaotic behaviour, a test suite is necessary.
370
722d2a37 371=head2 my sub foo { }
c47ff5f1 372
722d2a37 373The basic principle is sound, but there are problems with the semantics
374of self-referential and mutually referential lexical subs: how to
375declare the subs?
c47ff5f1 376
722d2a37 377=head2 One-pass global destruction
c47ff5f1 378
722d2a37 379Sweeping away all the allocated memory in one go is a laudable goal, but
380it's difficult and in most cases, it's easier to let the memory get
381freed by exiting.
e50bb9a1 382
722d2a37 383=head2 Rewrite regexp parser
e50bb9a1 384
722d2a37 385There has been talk recently of rewriting the regular expression parser
386to produce an optree instead of a chain of opcodes; it's unclear whether
387or not this would be a win.
e50bb9a1 388
722d2a37 389=head2 Cache recently used regexps
e50bb9a1 390
722d2a37 391This is to speed up
e50bb9a1 392
722d2a37 393 for my $re (@regexps) {
394 $matched++ if /$re/
395 }
e50bb9a1 396
722d2a37 397C<qr//> already gives us a way of saving compiled regexps, but it should
398be done automatically.
e50bb9a1 399
722d2a37 400=head2 Re-entrant functions
e50bb9a1 401
722d2a37 402Add configure probes for C<_r> forms of system calls and fit them to the
403core. Unfortunately, calling conventions for these functions and not
404standardised.
04c70446 405
722d2a37 406=head2 Cross-compilation support
04c70446 407
722d2a37 408Bart Schuller reports that using C<microperl> and a cross-compiler, he
409got Perl working on the Agenda PDA. However, one cannot build a full
410Perl because Configure needs to get the results for the target platform,
411for the host.
e50bb9a1 412
722d2a37 413=head2 Bit-shifting bitvectors
e50bb9a1 414
722d2a37 415Given:
e50bb9a1 416
722d2a37 417 vec($v, 1000, 1) = 1;
e50bb9a1 418
722d2a37 419One should be able to do
e50bb9a1 420
722d2a37 421 $v <<= 1;
e50bb9a1 422
722d2a37 423and have the 999'th bit set.
e50bb9a1 424
722d2a37 425Currently if you try with shift bitvectors you shift the NV/UV, instead
426of the bits in the PV. Not very logical.
e50bb9a1 427
722d2a37 428=head2 debugger pragma
e50bb9a1 429
722d2a37 430The debugger is implemented in Perl in F<perl5db.pl>; turning it into a
431pragma should be easy, but making it work lexically might be more
432difficult. Fiddling with C<$^P> would be necessary.
e50bb9a1 433
722d2a37 434=head2 use less pragma
e50bb9a1 435
722d2a37 436Identify areas where speed/memory tradeoffs can be made and have a hint
437to switch between them.
e50bb9a1 438
722d2a37 439=head2 switch structures
e50bb9a1 440
722d2a37 441Although we have C<Switch.pm> in core, Larry points to the dormant
442C<nswitch> and C<cswitch> ops in F<pp.c>; using these opcodes would be
443much faster.
e50bb9a1 444
722d2a37 445=head2 Cache eval tree
e50bb9a1 446
722d2a37 447=head2 rcatmaybe
e50bb9a1 448
722d2a37 449=head2 Shrink opcode tables
e50bb9a1 450
722d2a37 451=head2 Optimize away @_
e50bb9a1 452
722d2a37 453Look at the "reification" code in C<av.c>
e50bb9a1 454
722d2a37 455=head2 Prototypes versus indirect objects
e50bb9a1 456
722d2a37 457Currently, indirect object syntax bypasses prototype checks.
e50bb9a1 458
210b36aa 459=head2 Install HTML
e50bb9a1 460
722d2a37 461HTML versions of the documentation need to be installed by default; a
462call to C<installhtml> from C<installperl> may be all that's necessary.
e50bb9a1 463
722d2a37 464=head2 Prototype method calls
e50bb9a1 465
722d2a37 466=head2 Return context prototype declarations
e50bb9a1 467
722d2a37 468=head2 magic_setisa
e50bb9a1 469
722d2a37 470=head2 Garbage collection
e50bb9a1 471
722d2a37 472There have been persistent mumblings about putting a mark-and-sweep
473garbage detector into Perl; Alan Burlison has some ideas about this.
e50bb9a1 474
722d2a37 475=head2 IO tutorial
e50bb9a1 476
722d2a37 477Mark-Jason Dominus has the beginnings of one of these.
e50bb9a1 478
722d2a37 479=head2 Rewrite perldoc
e50bb9a1 480
722d2a37 481There are a few suggestions for what to do with C<perldoc>: maybe a
482full-text search, an index function, locating pages on a particular
483high-level subject, and so on.
e50bb9a1 484
3958b146 485=head2 Install .3p manpages
e50bb9a1 486
3958b146 487This is a bone of contention; we can create C<.3p> manpages for each
722d2a37 488built-in function, but should we install them by default? Tcl does this,
489and it clutters up C<apropos>.
e50bb9a1 490
722d2a37 491=head2 Unicode tutorial
e50bb9a1 492
722d2a37 493Simon Cozens promises to do this before he gets old.
e50bb9a1 494
722d2a37 495=head2 Update POSIX.pm for 1003.1-2
3958b146 496
722d2a37 497=head2 Retargetable installation
e50bb9a1 498
722d2a37 499Allow C<@INC> to be changed after Perl is built.
e50bb9a1 500
722d2a37 501=head2 POSIX emulation on non-POSIX systems
e50bb9a1 502
722d2a37 503Make C<POSIX.pm> behave as POSIXly as possible everywhere, meaning we
504have to implement POSIX equivalents for some functions if necessary.
e50bb9a1 505
722d2a37 506=head2 Rename Win32 headers
e50bb9a1 507
722d2a37 508=head2 Finish off lvalue functions
509
510They don't work in the debugger, and they don't work for list or hash
511slices.
e50bb9a1 512
722d2a37 513=head2 Update sprintf documentation
e50bb9a1 514
722d2a37 515Hugo van der Sanden plans to look at this.
e50bb9a1 516
722d2a37 517=head2 Use fchown/fchmod internally
e50bb9a1 518
722d2a37 519This has been done in places, but needs a thorough code review.
520Also fchdir is available in some platforms.
e50bb9a1 521
d45541b3 522=head2 Make v-strings overloaded objects
c5fc23ff 523
d45541b3 524Instead of having to guess whether a string is a v-string and thus
525needs to be displayed with %vd, make v-strings (readonly) objects
526(class "vstring"?) with a stringify overload.
c5fc23ff 527
49293501 528=head2 Allow restricted hash assignment
529
530Currently you're not allowed to assign to a restricted hash at all,
531even with the same keys.
532
533 %restricted = (foo => 42); # error
534
535This should be allowed if the new keyset is a subset of the old
536keyset. May require more extra code than we'd like in pp_aassign.
537
722d2a37 538=head1 Vague ideas
e50bb9a1 539
722d2a37 540Ideas which have been discussed, and which may or may not happen.
e50bb9a1 541
722d2a37 542=head2 ref() in list context
e50bb9a1 543
722d2a37 544It's unclear what this should do or how to do it without breaking old
545code.
e50bb9a1 546
f86a8bc5 547=head2 Make tr/// return histogram of characters in list context
e50bb9a1 548
722d2a37 549There is a patch for this, but it may require Unicodification.
e50bb9a1 550
722d2a37 551=head2 Compile to real threaded code
3958b146 552
722d2a37 553=head2 Structured types
3958b146 554
722d2a37 555=head2 Modifiable $1 et al.
e50bb9a1 556
722d2a37 557 ($x = "elephant") =~ /e(ph)/;
558 $1 = "g"; # $x = "elegant"
e50bb9a1 559
722d2a37 560What happens if there are multiple (nested?) brackets? What if the
561string changes between the match and the assignment?
e50bb9a1 562
722d2a37 563=head2 Procedural interfaces for IO::*, etc.
e50bb9a1 564
722d2a37 565Some core modules have been accused of being overly-OO. Adding
566procedural interfaces could demystify them.
e50bb9a1 567
722d2a37 568=head2 RPC modules
e50bb9a1 569
722d2a37 570=head2 Attach/detach debugger from running program
e50bb9a1 571
722d2a37 572With C<gdb>, you can attach the debugger to a running program if you
573pass the process ID. It would be good to do this with the Perl debugger
574on a running Perl program, although I'm not sure how it would be done.
e50bb9a1 575
722d2a37 576=head2 GUI::Native
e50bb9a1 577
722d2a37 578A non-core module that would use "native" GUI to create graphical
579applications.
e50bb9a1 580
722d2a37 581=head2 foreach(reverse ...)
e50bb9a1 582
722d2a37 583Currently
e50bb9a1 584
722d2a37 585 foreach (reverse @_) { ... }
e50bb9a1 586
722d2a37 587puts C<@_> on the stack, reverses it putting the reversed version on the
588stack, then iterates forwards. Instead, it could be special-cased to put
589C<@_> on the stack then iterate backwards.
e50bb9a1 590
722d2a37 591=head2 Constant function cache
e50bb9a1 592
722d2a37 593=head2 Approximate regular expression matching
e50bb9a1 594
722d2a37 595=head1 Ongoing
e50bb9a1 596
722d2a37 597These items B<always> need doing:
e50bb9a1 598
722d2a37 599=head2 Update guts documentation
e50bb9a1 600
722d2a37 601Simon Cozens tries to do this when possible, and contributions to the
602C<perlapi> documentation is welcome.
e50bb9a1 603
722d2a37 604=head2 Add more tests
e50bb9a1 605
722d2a37 606Michael Schwern will donate $500 to Yet Another Society when all core
607modules have tests.
e50bb9a1 608
722d2a37 609=head2 Update auxiliary tools
e50bb9a1 610
722d2a37 611The code we ship with Perl should look like good Perl 5.
e50bb9a1 612
722d2a37 613=head1 Recently done things
e50bb9a1 614
722d2a37 615These are things which have been on the todo lists in previous releases
616but have recently been completed.
e50bb9a1 617
b0b7f283 618=head2 Alternative RE syntax module
619
620The C<Regexp::English> module, available from the CPAN, provides this:
621
622 my $re = Regexp::English
623 -> start_of_line
624 -> literal('Flippers')
625 -> literal(':')
626 -> optional
627 -> whitespace_char
628 -> end
629 -> remember
630 -> multiple
631 -> digit;
632
633 /$re/;
634
722d2a37 635=head2 Safe signal handling
e50bb9a1 636
722d2a37 637A new signal model went into 5.7.1 without much fanfare. Operations and
638C<malloc>s are no longer interrupted by signals, which are handled
639between opcodes. This means that C<PERL_ASYNC_CHECK> now actually does
640something. However, there are still a few things that need to be done.
e50bb9a1 641
722d2a37 642=head2 Tie Modules
e50bb9a1 643
722d2a37 644Modules which implement arrays in terms of strings, substrings or files
645can be found on the CPAN.
e50bb9a1 646
722d2a37 647=head2 gettimeofday
e50bb9a1 648
210b36aa 649C<Time::HiRes> has been integrated into the core.
e50bb9a1 650
722d2a37 651=head2 setitimer and getimiter
e50bb9a1 652
210b36aa 653Adding C<Time::HiRes> got us this too.
e50bb9a1 654
722d2a37 655=head2 Testing __DIE__ hook
656
657Tests have been added.
658
659=head2 CPP equivalent in Perl
e50bb9a1 660
722d2a37 661A C Yardley will probably have done this by the time you can read this.
662This allows for a generalization of the C constant detection used in
663building C<Errno.pm>.
e50bb9a1 664
722d2a37 665=head2 Explicit switch statements
e50bb9a1 666
722d2a37 667C<Switch.pm> has been integrated into the core to give you all manner of
668C<switch...case> semantics.
e50bb9a1 669
722d2a37 670=head2 autocroak
e50bb9a1 671
722d2a37 672This is C<Fatal.pm>.
e50bb9a1 673
722d2a37 674=head2 UTF/EBCDIC
e50bb9a1 675
722d2a37 676Nick Ing-Simmons has made UTF-EBCDIC (UTR13) work with Perl.
e50bb9a1 677
722d2a37 678 EBCDIC? http://www.unicode.org/unicode/reports/tr16/
e50bb9a1 679
722d2a37 680=head2 UTF Regexes
e50bb9a1 681
722d2a37 682Although there are probably some small bugs to be rooted out, Jarkko
683Hietaniemi has made regular expressions polymorphic between bytes and
684characters.
e50bb9a1 685
722d2a37 686=head2 perlcc to produce executable
e50bb9a1 687
722d2a37 688C<perlcc> was recently rewritten, and can now produce standalone
689executables.
e50bb9a1 690
722d2a37 691=head2 END blocks saved in compiled output
e50bb9a1 692
722d2a37 693=head2 Secure temporary file module
e50bb9a1 694
722d2a37 695Tim Jenness' C<File::Temp> is now in core.
e50bb9a1 696
722d2a37 697=head2 Integrate Time::HiRes
e50bb9a1 698
722d2a37 699This module is now part of core.
e50bb9a1 700
722d2a37 701=head2 Turn Cwd into XS
e50bb9a1 702
722d2a37 703Benjamin Sugars has done this.
e50bb9a1 704
722d2a37 705=head2 Mmap for input
e50bb9a1 706
722d2a37 707Nick Ing-Simmons' C<perlio> supports an C<mmap> IO method.
e50bb9a1 708
722d2a37 709=head2 Byte to/from UTF8 and UTF8 to/from local conversion
e50bb9a1 710
722d2a37 711C<Encode> provides this.
e50bb9a1 712
722d2a37 713=head2 Add sockatmark support
e50bb9a1 714
722d2a37 715Added in 5.7.1
e50bb9a1 716
722d2a37 717=head2 Mailing list archives
718
719http://lists.perl.org/, http://archive.develooper.com/
720
721=head2 Bug tracking
722
723Richard Foley has written the bug tracking system at http://bugs.perl.org/
e50bb9a1 724
722d2a37 725=head2 Integrate MacPerl
e50bb9a1 726
722d2a37 727Chris Nandor and Matthias Neeracher have integrated the MacPerl changes
728into 5.6.0.
e50bb9a1 729
722d2a37 730=head2 Web "nerve center" for Perl
e50bb9a1 731
722d2a37 732http://use.perl.org/ is what you're looking for.
e50bb9a1 733
722d2a37 734=head2 Regular expression tutorial
e50bb9a1 735
722d2a37 736C<perlretut>, provided by Mark Kvale.
e50bb9a1 737
722d2a37 738=head2 Debugging Tutorial
e50bb9a1 739
722d2a37 740C<perldebtut>, written by Richard Foley.
e50bb9a1 741
722d2a37 742=head2 Integrate new modules
e50bb9a1 743
722d2a37 744Jarkko has been integrating madly into 5.7.x
e50bb9a1 745
722d2a37 746=head2 Integrate profiler
e50bb9a1 747
722d2a37 748C<Devel::DProf> is now a core module.
e50bb9a1 749
722d2a37 750=head2 Y2K error detection
e50bb9a1 751
722d2a37 752There's a configure option to detect unsafe concatenation with "19", and
753a CPAN module. (C<D'oh::Year>)
e50bb9a1 754
722d2a37 755=head2 Regular expression debugger
e50bb9a1 756
722d2a37 757While not part of core, Mark-Jason Dominus has written C<Rx> and has
758also come up with a generalised strategy for regular expression
759debugging.
e50bb9a1 760
722d2a37 761=head2 POD checker
e50bb9a1 762
722d2a37 763That's, uh, F<podchecker>
e50bb9a1 764
722d2a37 765=head2 "Dynamic" lexicals
e50bb9a1 766
722d2a37 767=head2 Cache precompiled modules
e50bb9a1 768
722d2a37 769=head1 Deprecated Wishes
e50bb9a1 770
722d2a37 771These are items which used to be in the todo file, but have been
772deprecated for some reason.
e50bb9a1 773
722d2a37 774=head2 Loop control on do{}
e50bb9a1 775
722d2a37 776This would break old code; use C<do{{ }}> instead.
e50bb9a1 777
722d2a37 778=head2 Lexically scoped typeglobs
e50bb9a1 779
722d2a37 780Not needed now we have lexical IO handles.
e50bb9a1 781
722d2a37 782=head2 format BOTTOM
3958b146 783
722d2a37 784=head2 report HANDLE
e50bb9a1 785
722d2a37 786Damian Conway's text formatting modules seem to be the Way To Go.
e50bb9a1 787
722d2a37 788=head2 Generalised want()/caller())
3958b146 789
638ae6a9 790Robin Houston's C<Want> module does this.
791
722d2a37 792=head2 Named prototypes
e50bb9a1 793
638ae6a9 794This seems to be delayed until Perl 6.
e50bb9a1 795
722d2a37 796=head2 Built-in globbing
e50bb9a1 797
722d2a37 798The C<File::Glob> module has been used to replace the C<glob> function.
e50bb9a1 799
722d2a37 800=head2 Regression tests for suidperl
e50bb9a1 801
722d2a37 802C<suidperl> is deprecated in favour of common sense.
e50bb9a1 803
722d2a37 804=head2 Cached hash values
e50bb9a1 805
722d2a37 806We have shared hash keys, which perform the same job.
e50bb9a1 807
722d2a37 808=head2 Add compression modules
e50bb9a1 809
722d2a37 810The compression modules are a little heavy; meanwhile, Nick Clark is
811working on experimental pragmata to do transparent decompression on
812input.
e50bb9a1 813
722d2a37 814=head2 Reorganise documentation into tutorials/references
e50bb9a1 815
722d2a37 816Could not get consensus on P5P about this.
e50bb9a1 817
722d2a37 818=head2 Remove distinction between functions and operators
819
820Caution: highly flammable.
821
822=head2 Make XS easier to use
e50bb9a1 823
722d2a37 824Use C<Inline> instead, or SWIG.
e50bb9a1 825
722d2a37 826=head2 Make embedding easier to use
e50bb9a1 827
722d2a37 828Use C<Inline::CPR>.
e50bb9a1 829
722d2a37 830=head2 man for perl
04c70446 831
722d2a37 832See the Perl Power Tools. (http://language.perl.com/ppt/)
04c70446 833
722d2a37 834=head2 my $Package::variable
04c70446 835
722d2a37 836Use C<our> instead.
04c70446 837
722d2a37 838=head2 "or" tests defined, not truth
04c70446 839
722d2a37 840Suggesting this on P5P B<will> cause a boring and interminable flamewar.
04c70446 841
722d2a37 842=head2 "class"-based lexicals
04c70446 843
cbb3fa72 844Use flyweight objects, secure hashes or, dare I say it, pseudo-hashes instead.
f86a8bc5 845(Or whatever will replace pseudohashes in 5.10.)
04c70446 846
722d2a37 847=head2 byteperl
04c70446 848
722d2a37 849C<ByteLoader> covers this.
04c70446 850
722d2a37 851=head2 Lazy evaluation / tail recursion removal
04c70446 852
f86a8bc5 853C<List::Util> gives first() (a short-circuiting grep); tail recursion
854removal is done manually, with C<goto &whoami;>. (However, MJD has
855found that C<goto &whoami> introduces a performance penalty, so maybe
856there should be a way to do this after all: C<sub foo {START: ... goto
857START;> is better.)
0562c0e3 858
859=head2 Make "use utf8" the default
860
f86a8bc5 861Because of backward compatibility this is difficult: scripts could not
862contain B<any legacy eight-bit data> (like Latin-1) anymore, even in
863string literals or pod. Also would introduce a measurable slowdown of
864at least few percentages since all regular expression operations would
865be done in full UTF-8. But if you want to try this, add
866-DUSE_UTF8_SCRIPTS to your compilation flags.
867
3298bd4d 868=head2 Unicode collation and normalization
869
870The Unicode::Collate and Unicode::Normalize modules
871by SADAHIRO Tomoyuki have been included since 5.8.0.
872
873 Collation? http://www.unicode.org/unicode/reports/tr10/
874 Normalization? http://www.unicode.org/unicode/reports/tr15/
0562c0e3 875
825b3abc 876=head2 Create debugging macros
877
878Debugging macros (like printsv, dump) can make debugging perl inside a
879C debugger much easier. A good set for gdb comes with mod_perl.
880Something similar should be distributed with perl.
881
882The proper way to do this is to use and extend Devel::DebugInit.
883Devel::DebugInit also needs to be extended to support threads.
884
885See p5p archives for late May/early June 2001 for a recent discussion
886on this topic.
887
b2ce4120 888=head2 truncate to the people
889
890One can emulate ftruncate() using F_FREESP and F_CHSIZ fcntls
891(see the UNIX FAQ for details). This needs to go somewhere near
892pp_sys.c:pp_truncate().
893
1626a787 894One can emulate truncate() easily if one has ftruncate().
895This emulation should also go near pp_sys.pp_truncate().
896
897=head2 pack/unpack tutorial
898
899Wolfgang Laun finished what Simon Cozens started.
900
3298bd4d 901=cut