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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
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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
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20C<perlio> provides this, but the interface could be a lot more
21straightforward.
e50bb9a1 22
4b3b956a 23=head2 Autoload bytes.pm
e50bb9a1 24
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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)
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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
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40Requirements: should handle both byte and UTF8 strings. isPRINT()
41characters printed as-is, character less than 256 as \xHH, Unicode
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42characters as \x{HHH}. Don't assume ASCII-like, either, get somebody
43on EBCDIC to test the output.
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44
45Possible options, controlled by the flags:
0661e9a4 46- whitespace (other than ' ' of isPRINT()) printed as-is
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47- use isPRINT_LC() instead of isPRINT()
48- print control characters like this: "\cA"
49- print control characters like this: "^A"
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50- non-PRINTables printed as '.' instead of \xHH
51- use \OOO instead of \xHH
52- use the C/Perl-metacharacters like \n, \t
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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
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57NOTE: pv_display(), pv_uni_display(), sv_uni_display() are doing
58something like the above.
59
722d2a37 60=head2 Overloadable regex assertions
e50bb9a1 61
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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
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67=head2 Unicode
68
69=over 4
70
71=item *
e50bb9a1 72
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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
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79Allow for the metaproperties: C<XID Start>, C<XID Continue>,
80C<NF*_NO>, C<NF*_MAYBE> (require the DerivedCoreProperties and
81DerviceNormalizationProperties files).
f34dec15 82
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83There are also multiple value properties still unimplemented:
84C<Numeric Type>, C<East Asian Width>.
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85
86=item *
87
722d2a37 88 Case Mappings? http://www.unicode.org/unicode/reports/tr21/
e50bb9a1 89
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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
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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
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102=back
103
104See L<perlunicode/UNICODE REGULAR EXPRESSION SUPPORT LEVEL> for what's
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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
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110Artur Bergman's C<iThreads> module is a start on this, but needs to
111be more mature.
e50bb9a1 112
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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
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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
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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
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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
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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
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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
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186All the code we ship with Perl needs to be sensible about temporary file
187handling, locking, input validation, and so on.
e50bb9a1 188
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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 $>, or vice versa, being
196uid==euid== zero, or just euid==zero, or as a normal user, what are
197the results?). The test suite not (usually) being run as root means
198that these things do not get much testing. Thirdly, there's quite
199often a third uid called saved uid, and Perl has no knowledge of that
200feature in any way. (If one has the saved uid of zero, one can get
201back any real and effective uids.) As an example, to change also the
202saved uid, one needs to set the real and effective uids B<twice>-- in
203most systems, that is: in HP-UX that doesn't seem to work.
204
722d2a37 205=head2 Custom opcodes
e50bb9a1 206
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207Have a way to introduce user-defined opcodes without the subroutine call
208overhead of an XSUB; the user should be able to create PP code. Simon
209Cozens has some ideas on this.
e50bb9a1 210
722d2a37 211=head2 DLL Versioning
e50bb9a1 212
d1be9408 213Windows needs a way to know what version of an XS or C<libperl> DLL it's
722d2a37 214loading.
e50bb9a1 215
722d2a37 216=head2 Introduce @( and @)
e50bb9a1 217
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218C<$(> 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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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 pack "(stuff)*"
e50bb9a1 307
722d2a37 308That's to say, C<pack "(sI)40"> would be the same as C<pack "sI"x40>
e50bb9a1 309
722d2a37 310=head2 bitfields in pack
e50bb9a1 311
722d2a37 312=head2 Cross compilation
e50bb9a1 313
722d2a37 314Make Perl buildable with a cross-compiler. This will play havoc with
da75cd15 315Configure, which needs to know how the target system will respond to
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316its tests; maybe C<microperl> will be a good starting point here.
317(Indeed, Bart Schuller reports that he compiled up C<microperl> for
318the Agenda PDA and it works fine.) A really big spanner in the works
319is the bootstrapping build process of Perl: if the filesystem the
320target systems sees is not the same what the build host sees, various
321input, output, and (Perl) library files need to be copied back and forth.
e50bb9a1 322
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323As of 5.8.0 Configure mostly works for cross-compilation
324(used successfully for iPAQ Linux), miniperl gets built,
325but then building DynaLoader (and other extensions) fails
326since MakeMaker knows nothing of cross-compilation.
327(See INSTALL/Cross-compilation for the state of things.)
328
722d2a37 329=head2 Perl preprocessor / macros
e50bb9a1 330
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331Source filters help with this, but do not get us all the way. For
332instance, it should be possible to implement the C<??> operator somehow;
333source filters don't (quite) cut it.
e50bb9a1 334
722d2a37 335=head2 Perl lexer in Perl
a45bd81d 336
722d2a37 337Damian Conway is planning to work on this, but it hasn't happened yet.
e50bb9a1 338
722d2a37 339=head2 Using POSIX calls internally
e50bb9a1 340
210b36aa 341When faced with a BSD vs. SysV -style interface to some library or
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342system function, perl's roots show in that it typically prefers the BSD
343interface (but falls back to the SysV one). One example is getpgrp().
344Other examples include C<memcpy> vs. C<bcopy>. There are others, mostly in
210b36aa 345F<pp_sys.c>.
e50bb9a1 346
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347Mostly, this item is a suggestion for which way to start a journey into
348an C<#ifdef> forest. It is not primarily a suggestion to eliminate any of
349the C<#ifdef> forests.
e50bb9a1 350
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351POSIX calls are perhaps more likely to be portable to unexpected
352architectures. They are also perhaps more likely to be actively
353maintained by a current vendor. They are also perhaps more likely to be
354available in thread-safe versions, if appropriate.
e50bb9a1 355
722d2a37 356=head2 -i rename file when changed
e50bb9a1 357
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358It's only necessary to rename a file when inplace editing when the file
359has changed. Detecting a change is perhaps the difficult bit.
e50bb9a1 360
722d2a37 361=head2 All ARGV input should act like E<lt>E<gt>
e50bb9a1 362
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363eg C<read(ARGV, ...)> doesn't currently read across multiple files.
364
722d2a37 365=head2 Support for rerunning debugger
e50bb9a1 366
722d2a37 367There should be a way of restarting the debugger on demand.
e50bb9a1 368
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369=head2 Test Suite for the Debugger
370
371The debugger is a complex piece of software and fixing something
372here may inadvertently break something else over there. To tame
373this chaotic behaviour, a test suite is necessary.
374
722d2a37 375=head2 my sub foo { }
c47ff5f1 376
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377The basic principle is sound, but there are problems with the semantics
378of self-referential and mutually referential lexical subs: how to
379declare the subs?
c47ff5f1 380
722d2a37 381=head2 One-pass global destruction
c47ff5f1 382
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383Sweeping away all the allocated memory in one go is a laudable goal, but
384it's difficult and in most cases, it's easier to let the memory get
385freed by exiting.
e50bb9a1 386
722d2a37 387=head2 Rewrite regexp parser
e50bb9a1 388
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389There has been talk recently of rewriting the regular expression parser
390to produce an optree instead of a chain of opcodes; it's unclear whether
391or not this would be a win.
e50bb9a1 392
722d2a37 393=head2 Cache recently used regexps
e50bb9a1 394
722d2a37 395This is to speed up
e50bb9a1 396
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397 for my $re (@regexps) {
398 $matched++ if /$re/
399 }
e50bb9a1 400
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401C<qr//> already gives us a way of saving compiled regexps, but it should
402be done automatically.
e50bb9a1 403
722d2a37 404=head2 Re-entrant functions
e50bb9a1 405
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406Add configure probes for C<_r> forms of system calls and fit them to the
407core. Unfortunately, calling conventions for these functions and not
408standardised.
04c70446 409
722d2a37 410=head2 Cross-compilation support
04c70446 411
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412Bart Schuller reports that using C<microperl> and a cross-compiler, he
413got Perl working on the Agenda PDA. However, one cannot build a full
414Perl because Configure needs to get the results for the target platform,
415for the host.
e50bb9a1 416
722d2a37 417=head2 Bit-shifting bitvectors
e50bb9a1 418
722d2a37 419Given:
e50bb9a1 420
722d2a37 421 vec($v, 1000, 1) = 1;
e50bb9a1 422
722d2a37 423One should be able to do
e50bb9a1 424
722d2a37 425 $v <<= 1;
e50bb9a1 426
722d2a37 427and have the 999'th bit set.
e50bb9a1 428
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429Currently if you try with shift bitvectors you shift the NV/UV, instead
430of the bits in the PV. Not very logical.
e50bb9a1 431
722d2a37 432=head2 debugger pragma
e50bb9a1 433
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434The debugger is implemented in Perl in F<perl5db.pl>; turning it into a
435pragma should be easy, but making it work lexically might be more
436difficult. Fiddling with C<$^P> would be necessary.
e50bb9a1 437
722d2a37 438=head2 use less pragma
e50bb9a1 439
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440Identify areas where speed/memory tradeoffs can be made and have a hint
441to switch between them.
e50bb9a1 442
722d2a37 443=head2 switch structures
e50bb9a1 444
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445Although we have C<Switch.pm> in core, Larry points to the dormant
446C<nswitch> and C<cswitch> ops in F<pp.c>; using these opcodes would be
447much faster.
e50bb9a1 448
722d2a37 449=head2 Cache eval tree
e50bb9a1 450
722d2a37 451=head2 rcatmaybe
e50bb9a1 452
722d2a37 453=head2 Shrink opcode tables
e50bb9a1 454
722d2a37 455=head2 Optimize away @_
e50bb9a1 456
722d2a37 457Look at the "reification" code in C<av.c>
e50bb9a1 458
722d2a37 459=head2 Prototypes versus indirect objects
e50bb9a1 460
722d2a37 461Currently, indirect object syntax bypasses prototype checks.
e50bb9a1 462
210b36aa 463=head2 Install HTML
e50bb9a1 464
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465HTML versions of the documentation need to be installed by default; a
466call to C<installhtml> from C<installperl> may be all that's necessary.
e50bb9a1 467
722d2a37 468=head2 Prototype method calls
e50bb9a1 469
722d2a37 470=head2 Return context prototype declarations
e50bb9a1 471
722d2a37 472=head2 magic_setisa
e50bb9a1 473
722d2a37 474=head2 Garbage collection
e50bb9a1 475
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476There have been persistent mumblings about putting a mark-and-sweep
477garbage detector into Perl; Alan Burlison has some ideas about this.
e50bb9a1 478
722d2a37 479=head2 IO tutorial
e50bb9a1 480
722d2a37 481Mark-Jason Dominus has the beginnings of one of these.
e50bb9a1 482
722d2a37 483=head2 pack/unpack tutorial
e50bb9a1 484
722d2a37 485Simon Cozens has the beginnings of one of these.
e50bb9a1 486
722d2a37 487=head2 Rewrite perldoc
e50bb9a1 488
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489There are a few suggestions for what to do with C<perldoc>: maybe a
490full-text search, an index function, locating pages on a particular
491high-level subject, and so on.
e50bb9a1 492
3958b146 493=head2 Install .3p manpages
e50bb9a1 494
3958b146 495This is a bone of contention; we can create C<.3p> manpages for each
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496built-in function, but should we install them by default? Tcl does this,
497and it clutters up C<apropos>.
e50bb9a1 498
722d2a37 499=head2 Unicode tutorial
e50bb9a1 500
722d2a37 501Simon Cozens promises to do this before he gets old.
e50bb9a1 502
722d2a37 503=head2 Update POSIX.pm for 1003.1-2
3958b146 504
722d2a37 505=head2 Retargetable installation
e50bb9a1 506
722d2a37 507Allow C<@INC> to be changed after Perl is built.
e50bb9a1 508
722d2a37 509=head2 POSIX emulation on non-POSIX systems
e50bb9a1 510
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511Make C<POSIX.pm> behave as POSIXly as possible everywhere, meaning we
512have to implement POSIX equivalents for some functions if necessary.
e50bb9a1 513
722d2a37 514=head2 Rename Win32 headers
e50bb9a1 515
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516=head2 Finish off lvalue functions
517
518They don't work in the debugger, and they don't work for list or hash
519slices.
e50bb9a1 520
722d2a37 521=head2 Update sprintf documentation
e50bb9a1 522
722d2a37 523Hugo van der Sanden plans to look at this.
e50bb9a1 524
722d2a37 525=head2 Use fchown/fchmod internally
e50bb9a1 526
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527This has been done in places, but needs a thorough code review.
528Also fchdir is available in some platforms.
e50bb9a1 529
d45541b3 530=head2 Make v-strings overloaded objects
c5fc23ff 531
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532Instead of having to guess whether a string is a v-string and thus
533needs to be displayed with %vd, make v-strings (readonly) objects
534(class "vstring"?) with a stringify overload.
c5fc23ff 535
722d2a37 536=head1 Vague ideas
e50bb9a1 537
722d2a37 538Ideas which have been discussed, and which may or may not happen.
e50bb9a1 539
722d2a37 540=head2 ref() in list context
e50bb9a1 541
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542It's unclear what this should do or how to do it without breaking old
543code.
e50bb9a1 544
f86a8bc5 545=head2 Make tr/// return histogram of characters in list context
e50bb9a1 546
722d2a37 547There is a patch for this, but it may require Unicodification.
e50bb9a1 548
722d2a37 549=head2 Compile to real threaded code
3958b146 550
722d2a37 551=head2 Structured types
3958b146 552
722d2a37 553=head2 Modifiable $1 et al.
e50bb9a1 554
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555 ($x = "elephant") =~ /e(ph)/;
556 $1 = "g"; # $x = "elegant"
e50bb9a1 557
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558What happens if there are multiple (nested?) brackets? What if the
559string changes between the match and the assignment?
e50bb9a1 560
722d2a37 561=head2 Procedural interfaces for IO::*, etc.
e50bb9a1 562
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563Some core modules have been accused of being overly-OO. Adding
564procedural interfaces could demystify them.
e50bb9a1 565
722d2a37 566=head2 RPC modules
e50bb9a1 567
722d2a37 568=head2 Attach/detach debugger from running program
e50bb9a1 569
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570With C<gdb>, you can attach the debugger to a running program if you
571pass the process ID. It would be good to do this with the Perl debugger
572on a running Perl program, although I'm not sure how it would be done.
e50bb9a1 573
722d2a37 574=head2 Alternative RE syntax module
e50bb9a1 575
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576 use Regex::Newbie;
577 $re = Regex::Newbie->new
578 ->start
579 ->match("foo")
580 ->repeat(Regex::Newbie->class("char"),3)
581 ->end;
582 /$re/;
e50bb9a1 583
722d2a37 584=head2 GUI::Native
e50bb9a1 585
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586A non-core module that would use "native" GUI to create graphical
587applications.
e50bb9a1 588
722d2a37 589=head2 foreach(reverse ...)
e50bb9a1 590
722d2a37 591Currently
e50bb9a1 592
722d2a37 593 foreach (reverse @_) { ... }
e50bb9a1 594
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595puts C<@_> on the stack, reverses it putting the reversed version on the
596stack, then iterates forwards. Instead, it could be special-cased to put
597C<@_> on the stack then iterate backwards.
e50bb9a1 598
722d2a37 599=head2 Constant function cache
e50bb9a1 600
722d2a37 601=head2 Approximate regular expression matching
e50bb9a1 602
722d2a37 603=head1 Ongoing
e50bb9a1 604
722d2a37 605These items B<always> need doing:
e50bb9a1 606
722d2a37 607=head2 Update guts documentation
e50bb9a1 608
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609Simon Cozens tries to do this when possible, and contributions to the
610C<perlapi> documentation is welcome.
e50bb9a1 611
722d2a37 612=head2 Add more tests
e50bb9a1 613
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614Michael Schwern will donate $500 to Yet Another Society when all core
615modules have tests.
e50bb9a1 616
722d2a37 617=head2 Update auxiliary tools
e50bb9a1 618
722d2a37 619The code we ship with Perl should look like good Perl 5.
e50bb9a1 620
722d2a37 621=head1 Recently done things
e50bb9a1 622
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623These are things which have been on the todo lists in previous releases
624but have recently been completed.
e50bb9a1 625
722d2a37 626=head2 Safe signal handling
e50bb9a1 627
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628A new signal model went into 5.7.1 without much fanfare. Operations and
629C<malloc>s are no longer interrupted by signals, which are handled
630between opcodes. This means that C<PERL_ASYNC_CHECK> now actually does
631something. However, there are still a few things that need to be done.
e50bb9a1 632
722d2a37 633=head2 Tie Modules
e50bb9a1 634
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635Modules which implement arrays in terms of strings, substrings or files
636can be found on the CPAN.
e50bb9a1 637
722d2a37 638=head2 gettimeofday
e50bb9a1 639
210b36aa 640C<Time::HiRes> has been integrated into the core.
e50bb9a1 641
722d2a37 642=head2 setitimer and getimiter
e50bb9a1 643
210b36aa 644Adding C<Time::HiRes> got us this too.
e50bb9a1 645
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646=head2 Testing __DIE__ hook
647
648Tests have been added.
649
650=head2 CPP equivalent in Perl
e50bb9a1 651
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652A C Yardley will probably have done this by the time you can read this.
653This allows for a generalization of the C constant detection used in
654building C<Errno.pm>.
e50bb9a1 655
722d2a37 656=head2 Explicit switch statements
e50bb9a1 657
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658C<Switch.pm> has been integrated into the core to give you all manner of
659C<switch...case> semantics.
e50bb9a1 660
722d2a37 661=head2 autocroak
e50bb9a1 662
722d2a37 663This is C<Fatal.pm>.
e50bb9a1 664
722d2a37 665=head2 UTF/EBCDIC
e50bb9a1 666
722d2a37 667Nick Ing-Simmons has made UTF-EBCDIC (UTR13) work with Perl.
e50bb9a1 668
722d2a37 669 EBCDIC? http://www.unicode.org/unicode/reports/tr16/
e50bb9a1 670
722d2a37 671=head2 UTF Regexes
e50bb9a1 672
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673Although there are probably some small bugs to be rooted out, Jarkko
674Hietaniemi has made regular expressions polymorphic between bytes and
675characters.
e50bb9a1 676
722d2a37 677=head2 perlcc to produce executable
e50bb9a1 678
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679C<perlcc> was recently rewritten, and can now produce standalone
680executables.
e50bb9a1 681
722d2a37 682=head2 END blocks saved in compiled output
e50bb9a1 683
722d2a37 684=head2 Secure temporary file module
e50bb9a1 685
722d2a37 686Tim Jenness' C<File::Temp> is now in core.
e50bb9a1 687
722d2a37 688=head2 Integrate Time::HiRes
e50bb9a1 689
722d2a37 690This module is now part of core.
e50bb9a1 691
722d2a37 692=head2 Turn Cwd into XS
e50bb9a1 693
722d2a37 694Benjamin Sugars has done this.
e50bb9a1 695
722d2a37 696=head2 Mmap for input
e50bb9a1 697
722d2a37 698Nick Ing-Simmons' C<perlio> supports an C<mmap> IO method.
e50bb9a1 699
722d2a37 700=head2 Byte to/from UTF8 and UTF8 to/from local conversion
e50bb9a1 701
722d2a37 702C<Encode> provides this.
e50bb9a1 703
722d2a37 704=head2 Add sockatmark support
e50bb9a1 705
722d2a37 706Added in 5.7.1
e50bb9a1 707
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708=head2 Mailing list archives
709
710http://lists.perl.org/, http://archive.develooper.com/
711
712=head2 Bug tracking
713
714Richard Foley has written the bug tracking system at http://bugs.perl.org/
e50bb9a1 715
722d2a37 716=head2 Integrate MacPerl
e50bb9a1 717
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718Chris Nandor and Matthias Neeracher have integrated the MacPerl changes
719into 5.6.0.
e50bb9a1 720
722d2a37 721=head2 Web "nerve center" for Perl
e50bb9a1 722
722d2a37 723http://use.perl.org/ is what you're looking for.
e50bb9a1 724
722d2a37 725=head2 Regular expression tutorial
e50bb9a1 726
722d2a37 727C<perlretut>, provided by Mark Kvale.
e50bb9a1 728
722d2a37 729=head2 Debugging Tutorial
e50bb9a1 730
722d2a37 731C<perldebtut>, written by Richard Foley.
e50bb9a1 732
722d2a37 733=head2 Integrate new modules
e50bb9a1 734
722d2a37 735Jarkko has been integrating madly into 5.7.x
e50bb9a1 736
722d2a37 737=head2 Integrate profiler
e50bb9a1 738
722d2a37 739C<Devel::DProf> is now a core module.
e50bb9a1 740
722d2a37 741=head2 Y2K error detection
e50bb9a1 742
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743There's a configure option to detect unsafe concatenation with "19", and
744a CPAN module. (C<D'oh::Year>)
e50bb9a1 745
722d2a37 746=head2 Regular expression debugger
e50bb9a1 747
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748While not part of core, Mark-Jason Dominus has written C<Rx> and has
749also come up with a generalised strategy for regular expression
750debugging.
e50bb9a1 751
722d2a37 752=head2 POD checker
e50bb9a1 753
722d2a37 754That's, uh, F<podchecker>
e50bb9a1 755
722d2a37 756=head2 "Dynamic" lexicals
e50bb9a1 757
722d2a37 758=head2 Cache precompiled modules
e50bb9a1 759
722d2a37 760=head1 Deprecated Wishes
e50bb9a1 761
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762These are items which used to be in the todo file, but have been
763deprecated for some reason.
e50bb9a1 764
722d2a37 765=head2 Loop control on do{}
e50bb9a1 766
722d2a37 767This would break old code; use C<do{{ }}> instead.
e50bb9a1 768
722d2a37 769=head2 Lexically scoped typeglobs
e50bb9a1 770
722d2a37 771Not needed now we have lexical IO handles.
e50bb9a1 772
722d2a37 773=head2 format BOTTOM
3958b146 774
722d2a37 775=head2 report HANDLE
e50bb9a1 776
722d2a37 777Damian Conway's text formatting modules seem to be the Way To Go.
e50bb9a1 778
722d2a37 779=head2 Generalised want()/caller())
3958b146 780
722d2a37 781=head2 Named prototypes
e50bb9a1 782
722d2a37 783These both seem to be delayed until Perl 6.
e50bb9a1 784
722d2a37 785=head2 Built-in globbing
e50bb9a1 786
722d2a37 787The C<File::Glob> module has been used to replace the C<glob> function.
e50bb9a1 788
722d2a37 789=head2 Regression tests for suidperl
e50bb9a1 790
722d2a37 791C<suidperl> is deprecated in favour of common sense.
e50bb9a1 792
722d2a37 793=head2 Cached hash values
e50bb9a1 794
722d2a37 795We have shared hash keys, which perform the same job.
e50bb9a1 796
722d2a37 797=head2 Add compression modules
e50bb9a1 798
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799The compression modules are a little heavy; meanwhile, Nick Clark is
800working on experimental pragmata to do transparent decompression on
801input.
e50bb9a1 802
722d2a37 803=head2 Reorganise documentation into tutorials/references
e50bb9a1 804
722d2a37 805Could not get consensus on P5P about this.
e50bb9a1 806
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807=head2 Remove distinction between functions and operators
808
809Caution: highly flammable.
810
811=head2 Make XS easier to use
e50bb9a1 812
722d2a37 813Use C<Inline> instead, or SWIG.
e50bb9a1 814
722d2a37 815=head2 Make embedding easier to use
e50bb9a1 816
722d2a37 817Use C<Inline::CPR>.
e50bb9a1 818
722d2a37 819=head2 man for perl
04c70446 820
722d2a37 821See the Perl Power Tools. (http://language.perl.com/ppt/)
04c70446 822
722d2a37 823=head2 my $Package::variable
04c70446 824
722d2a37 825Use C<our> instead.
04c70446 826
722d2a37 827=head2 "or" tests defined, not truth
04c70446 828
722d2a37 829Suggesting this on P5P B<will> cause a boring and interminable flamewar.
04c70446 830
722d2a37 831=head2 "class"-based lexicals
04c70446 832
cbb3fa72 833Use flyweight objects, secure hashes or, dare I say it, pseudo-hashes instead.
f86a8bc5 834(Or whatever will replace pseudohashes in 5.10.)
04c70446 835
722d2a37 836=head2 byteperl
04c70446 837
722d2a37 838C<ByteLoader> covers this.
04c70446 839
722d2a37 840=head2 Lazy evaluation / tail recursion removal
04c70446 841
f86a8bc5
JH
842C<List::Util> gives first() (a short-circuiting grep); tail recursion
843removal is done manually, with C<goto &whoami;>. (However, MJD has
844found that C<goto &whoami> introduces a performance penalty, so maybe
845there should be a way to do this after all: C<sub foo {START: ... goto
846START;> is better.)
0562c0e3
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847
848=head2 Make "use utf8" the default
849
f86a8bc5
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850Because of backward compatibility this is difficult: scripts could not
851contain B<any legacy eight-bit data> (like Latin-1) anymore, even in
852string literals or pod. Also would introduce a measurable slowdown of
853at least few percentages since all regular expression operations would
854be done in full UTF-8. But if you want to try this, add
855-DUSE_UTF8_SCRIPTS to your compilation flags.
856
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857=head2 Unicode collation and normalization
858
859The Unicode::Collate and Unicode::Normalize modules
860by SADAHIRO Tomoyuki have been included since 5.8.0.
861
862 Collation? http://www.unicode.org/unicode/reports/tr10/
863 Normalization? http://www.unicode.org/unicode/reports/tr15/
0562c0e3 864
825b3abc
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865=head2 Create debugging macros
866
867Debugging macros (like printsv, dump) can make debugging perl inside a
868C debugger much easier. A good set for gdb comes with mod_perl.
869Something similar should be distributed with perl.
870
871The proper way to do this is to use and extend Devel::DebugInit.
872Devel::DebugInit also needs to be extended to support threads.
873
874See p5p archives for late May/early June 2001 for a recent discussion
875on this topic.
876
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877=head2 truncate to the people
878
879One can emulate ftruncate() using F_FREESP and F_CHSIZ fcntls
880(see the UNIX FAQ for details). This needs to go somewhere near
881pp_sys.c:pp_truncate().
882
3298bd4d 883=cut