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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 already
58doing something like the above.
c5fc23ff 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 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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
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393 for my $re (@regexps) {
394 $matched++ if /$re/
395 }
e50bb9a1 396
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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
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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
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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 $v <<= 1;
e50bb9a1 422
722d2a37 423and have the 999'th bit set.
e50bb9a1 424
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425Currently if you try with shift bitvectors you shift the NV/UV, instead
426of the bits in the PV. Not very logical.
e50bb9a1 427
722d2a37 428=head2 debugger pragma
e50bb9a1 429
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430The debugger is implemented in Perl in F<perl5db.pl>; turning it into a
431pragma should be easy, but making it work lexically might be more
432difficult. Fiddling with C<$^P> would be necessary.
e50bb9a1 433
722d2a37 434=head2 use less pragma
e50bb9a1 435
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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
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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
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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
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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
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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
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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
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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
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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
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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
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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
722d2a37 528=head1 Vague ideas
e50bb9a1 529
722d2a37 530Ideas which have been discussed, and which may or may not happen.
e50bb9a1 531
722d2a37 532=head2 ref() in list context
e50bb9a1 533
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534It's unclear what this should do or how to do it without breaking old
535code.
e50bb9a1 536
f86a8bc5 537=head2 Make tr/// return histogram of characters in list context
e50bb9a1 538
722d2a37 539There is a patch for this, but it may require Unicodification.
e50bb9a1 540
722d2a37 541=head2 Compile to real threaded code
3958b146 542
722d2a37 543=head2 Structured types
3958b146 544
722d2a37 545=head2 Modifiable $1 et al.
e50bb9a1 546
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547 ($x = "elephant") =~ /e(ph)/;
548 $1 = "g"; # $x = "elegant"
e50bb9a1 549
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550What happens if there are multiple (nested?) brackets? What if the
551string changes between the match and the assignment?
e50bb9a1 552
722d2a37 553=head2 Procedural interfaces for IO::*, etc.
e50bb9a1 554
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555Some core modules have been accused of being overly-OO. Adding
556procedural interfaces could demystify them.
e50bb9a1 557
722d2a37 558=head2 RPC modules
e50bb9a1 559
722d2a37 560=head2 Attach/detach debugger from running program
e50bb9a1 561
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562With C<gdb>, you can attach the debugger to a running program if you
563pass the process ID. It would be good to do this with the Perl debugger
564on a running Perl program, although I'm not sure how it would be done.
e50bb9a1 565
722d2a37 566=head2 GUI::Native
e50bb9a1 567
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568A non-core module that would use "native" GUI to create graphical
569applications.
e50bb9a1 570
722d2a37 571=head2 foreach(reverse ...)
e50bb9a1 572
722d2a37 573Currently
e50bb9a1 574
722d2a37 575 foreach (reverse @_) { ... }
e50bb9a1 576
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577puts C<@_> on the stack, reverses it putting the reversed version on the
578stack, then iterates forwards. Instead, it could be special-cased to put
579C<@_> on the stack then iterate backwards.
e50bb9a1 580
722d2a37 581=head2 Constant function cache
e50bb9a1 582
722d2a37 583=head2 Approximate regular expression matching
e50bb9a1 584
722d2a37 585=head1 Ongoing
e50bb9a1 586
722d2a37 587These items B<always> need doing:
e50bb9a1 588
722d2a37 589=head2 Update guts documentation
e50bb9a1 590
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591Simon Cozens tries to do this when possible, and contributions to the
592C<perlapi> documentation is welcome.
e50bb9a1 593
722d2a37 594=head2 Add more tests
e50bb9a1 595
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596Michael Schwern will donate $500 to Yet Another Society when all core
597modules have tests.
e50bb9a1 598
722d2a37 599=head2 Update auxiliary tools
e50bb9a1 600
722d2a37 601The code we ship with Perl should look like good Perl 5.
e50bb9a1 602
722d2a37 603=head1 Recently done things
e50bb9a1 604
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605These are things which have been on the todo lists in previous releases
606but have recently been completed.
e50bb9a1 607
b0b7f283 608=head2 Alternative RE syntax module
609
610The C<Regexp::English> module, available from the CPAN, provides this:
611
612 my $re = Regexp::English
613 -> start_of_line
614 -> literal('Flippers')
615 -> literal(':')
616 -> optional
617 -> whitespace_char
618 -> end
619 -> remember
620 -> multiple
621 -> digit;
622
623 /$re/;
624
722d2a37 625=head2 Safe signal handling
e50bb9a1 626
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627A new signal model went into 5.7.1 without much fanfare. Operations and
628C<malloc>s are no longer interrupted by signals, which are handled
629between opcodes. This means that C<PERL_ASYNC_CHECK> now actually does
630something. However, there are still a few things that need to be done.
e50bb9a1 631
722d2a37 632=head2 Tie Modules
e50bb9a1 633
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634Modules which implement arrays in terms of strings, substrings or files
635can be found on the CPAN.
e50bb9a1 636
722d2a37 637=head2 gettimeofday
e50bb9a1 638
210b36aa 639C<Time::HiRes> has been integrated into the core.
e50bb9a1 640
722d2a37 641=head2 setitimer and getimiter
e50bb9a1 642
210b36aa 643Adding C<Time::HiRes> got us this too.
e50bb9a1 644
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645=head2 Testing __DIE__ hook
646
647Tests have been added.
648
649=head2 CPP equivalent in Perl
e50bb9a1 650
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651A C Yardley will probably have done this by the time you can read this.
652This allows for a generalization of the C constant detection used in
653building C<Errno.pm>.
e50bb9a1 654
722d2a37 655=head2 Explicit switch statements
e50bb9a1 656
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657C<Switch.pm> has been integrated into the core to give you all manner of
658C<switch...case> semantics.
e50bb9a1 659
722d2a37 660=head2 autocroak
e50bb9a1 661
722d2a37 662This is C<Fatal.pm>.
e50bb9a1 663
722d2a37 664=head2 UTF/EBCDIC
e50bb9a1 665
722d2a37 666Nick Ing-Simmons has made UTF-EBCDIC (UTR13) work with Perl.
e50bb9a1 667
722d2a37 668 EBCDIC? http://www.unicode.org/unicode/reports/tr16/
e50bb9a1 669
722d2a37 670=head2 UTF Regexes
e50bb9a1 671
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672Although there are probably some small bugs to be rooted out, Jarkko
673Hietaniemi has made regular expressions polymorphic between bytes and
674characters.
e50bb9a1 675
722d2a37 676=head2 perlcc to produce executable
e50bb9a1 677
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678C<perlcc> was recently rewritten, and can now produce standalone
679executables.
e50bb9a1 680
722d2a37 681=head2 END blocks saved in compiled output
e50bb9a1 682
722d2a37 683=head2 Secure temporary file module
e50bb9a1 684
722d2a37 685Tim Jenness' C<File::Temp> is now in core.
e50bb9a1 686
722d2a37 687=head2 Integrate Time::HiRes
e50bb9a1 688
722d2a37 689This module is now part of core.
e50bb9a1 690
722d2a37 691=head2 Turn Cwd into XS
e50bb9a1 692
722d2a37 693Benjamin Sugars has done this.
e50bb9a1 694
722d2a37 695=head2 Mmap for input
e50bb9a1 696
722d2a37 697Nick Ing-Simmons' C<perlio> supports an C<mmap> IO method.
e50bb9a1 698
722d2a37 699=head2 Byte to/from UTF8 and UTF8 to/from local conversion
e50bb9a1 700
722d2a37 701C<Encode> provides this.
e50bb9a1 702
722d2a37 703=head2 Add sockatmark support
e50bb9a1 704
722d2a37 705Added in 5.7.1
e50bb9a1 706
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707=head2 Mailing list archives
708
709http://lists.perl.org/, http://archive.develooper.com/
710
711=head2 Bug tracking
712
713Richard Foley has written the bug tracking system at http://bugs.perl.org/
e50bb9a1 714
722d2a37 715=head2 Integrate MacPerl
e50bb9a1 716
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717Chris Nandor and Matthias Neeracher have integrated the MacPerl changes
718into 5.6.0.
e50bb9a1 719
722d2a37 720=head2 Web "nerve center" for Perl
e50bb9a1 721
722d2a37 722http://use.perl.org/ is what you're looking for.
e50bb9a1 723
722d2a37 724=head2 Regular expression tutorial
e50bb9a1 725
722d2a37 726C<perlretut>, provided by Mark Kvale.
e50bb9a1 727
722d2a37 728=head2 Debugging Tutorial
e50bb9a1 729
722d2a37 730C<perldebtut>, written by Richard Foley.
e50bb9a1 731
722d2a37 732=head2 Integrate new modules
e50bb9a1 733
722d2a37 734Jarkko has been integrating madly into 5.7.x
e50bb9a1 735
722d2a37 736=head2 Integrate profiler
e50bb9a1 737
722d2a37 738C<Devel::DProf> is now a core module.
e50bb9a1 739
722d2a37 740=head2 Y2K error detection
e50bb9a1 741
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742There's a configure option to detect unsafe concatenation with "19", and
743a CPAN module. (C<D'oh::Year>)
e50bb9a1 744
722d2a37 745=head2 Regular expression debugger
e50bb9a1 746
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747While not part of core, Mark-Jason Dominus has written C<Rx> and has
748also come up with a generalised strategy for regular expression
749debugging.
e50bb9a1 750
722d2a37 751=head2 POD checker
e50bb9a1 752
722d2a37 753That's, uh, F<podchecker>
e50bb9a1 754
722d2a37 755=head2 "Dynamic" lexicals
e50bb9a1 756
722d2a37 757=head2 Cache precompiled modules
e50bb9a1 758
722d2a37 759=head1 Deprecated Wishes
e50bb9a1 760
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761These are items which used to be in the todo file, but have been
762deprecated for some reason.
e50bb9a1 763
722d2a37 764=head2 Loop control on do{}
e50bb9a1 765
722d2a37 766This would break old code; use C<do{{ }}> instead.
e50bb9a1 767
722d2a37 768=head2 Lexically scoped typeglobs
e50bb9a1 769
722d2a37 770Not needed now we have lexical IO handles.
e50bb9a1 771
722d2a37 772=head2 format BOTTOM
3958b146 773
722d2a37 774=head2 report HANDLE
e50bb9a1 775
722d2a37 776Damian Conway's text formatting modules seem to be the Way To Go.
e50bb9a1 777
722d2a37 778=head2 Generalised want()/caller())
3958b146 779
722d2a37 780=head2 Named prototypes
e50bb9a1 781
722d2a37 782These both seem to be delayed until Perl 6.
e50bb9a1 783
722d2a37 784=head2 Built-in globbing
e50bb9a1 785
722d2a37 786The C<File::Glob> module has been used to replace the C<glob> function.
e50bb9a1 787
722d2a37 788=head2 Regression tests for suidperl
e50bb9a1 789
722d2a37 790C<suidperl> is deprecated in favour of common sense.
e50bb9a1 791
722d2a37 792=head2 Cached hash values
e50bb9a1 793
722d2a37 794We have shared hash keys, which perform the same job.
e50bb9a1 795
722d2a37 796=head2 Add compression modules
e50bb9a1 797
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798The compression modules are a little heavy; meanwhile, Nick Clark is
799working on experimental pragmata to do transparent decompression on
800input.
e50bb9a1 801
722d2a37 802=head2 Reorganise documentation into tutorials/references
e50bb9a1 803
722d2a37 804Could not get consensus on P5P about this.
e50bb9a1 805
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806=head2 Remove distinction between functions and operators
807
808Caution: highly flammable.
809
810=head2 Make XS easier to use
e50bb9a1 811
722d2a37 812Use C<Inline> instead, or SWIG.
e50bb9a1 813
722d2a37 814=head2 Make embedding easier to use
e50bb9a1 815
722d2a37 816Use C<Inline::CPR>.
e50bb9a1 817
722d2a37 818=head2 man for perl
04c70446 819
722d2a37 820See the Perl Power Tools. (http://language.perl.com/ppt/)
04c70446 821
722d2a37 822=head2 my $Package::variable
04c70446 823
722d2a37 824Use C<our> instead.
04c70446 825
722d2a37 826=head2 "or" tests defined, not truth
04c70446 827
722d2a37 828Suggesting this on P5P B<will> cause a boring and interminable flamewar.
04c70446 829
722d2a37 830=head2 "class"-based lexicals
04c70446 831
cbb3fa72 832Use flyweight objects, secure hashes or, dare I say it, pseudo-hashes instead.
f86a8bc5 833(Or whatever will replace pseudohashes in 5.10.)
04c70446 834
722d2a37 835=head2 byteperl
04c70446 836
722d2a37 837C<ByteLoader> covers this.
04c70446 838
722d2a37 839=head2 Lazy evaluation / tail recursion removal
04c70446 840
f86a8bc5
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841C<List::Util> gives first() (a short-circuiting grep); tail recursion
842removal is done manually, with C<goto &whoami;>. (However, MJD has
843found that C<goto &whoami> introduces a performance penalty, so maybe
844there should be a way to do this after all: C<sub foo {START: ... goto
845START;> is better.)
0562c0e3
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846
847=head2 Make "use utf8" the default
848
f86a8bc5
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849Because of backward compatibility this is difficult: scripts could not
850contain B<any legacy eight-bit data> (like Latin-1) anymore, even in
851string literals or pod. Also would introduce a measurable slowdown of
852at least few percentages since all regular expression operations would
853be done in full UTF-8. But if you want to try this, add
854-DUSE_UTF8_SCRIPTS to your compilation flags.
855
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856=head2 Unicode collation and normalization
857
858The Unicode::Collate and Unicode::Normalize modules
859by SADAHIRO Tomoyuki have been included since 5.8.0.
860
861 Collation? http://www.unicode.org/unicode/reports/tr10/
862 Normalization? http://www.unicode.org/unicode/reports/tr15/
0562c0e3 863
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864=head2 Create debugging macros
865
866Debugging macros (like printsv, dump) can make debugging perl inside a
867C debugger much easier. A good set for gdb comes with mod_perl.
868Something similar should be distributed with perl.
869
870The proper way to do this is to use and extend Devel::DebugInit.
871Devel::DebugInit also needs to be extended to support threads.
872
873See p5p archives for late May/early June 2001 for a recent discussion
874on this topic.
875
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876=head2 truncate to the people
877
878One can emulate ftruncate() using F_FREESP and F_CHSIZ fcntls
879(see the UNIX FAQ for details). This needs to go somewhere near
880pp_sys.c:pp_truncate().
881
1626a787
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882One can emulate truncate() easily if one has ftruncate().
883This emulation should also go near pp_sys.pp_truncate().
884
885=head2 pack/unpack tutorial
886
887Wolfgang Laun finished what Simon Cozens started.
888
3298bd4d 889=cut