C<perlio> provides this, but the interface could be a lot more
straightforward.
-=head2 Eliminate need for "use utf8";
-
-While the C<utf8> pragma is autoloaded when necessary, it's still needed
-for things like Unicode characters in a source file. The UTF8 hint can
-always be set to true, but it needs to be set to false when F<utf8.pm>
-is being compiled. (To stop Perl trying to autoload the C<utf8>
-pragma...)
-
-=head2 Autoload byte.pm
+=head2 Autoload bytes.pm
When the lexer sees, for instance, C<bytes::length>, it should
automatically load the C<bytes> pragma.
C<"\xF00"> and C<"\U{F00}"> on P5P I<will> lead to a long and boring
flamewar.
+=head2 Create a char *sv_pvprintify(sv, STRLEN *lenp, UV flags)
+
+For displaying PVs with control characters, embedded nulls, and Unicode.
+This would be useful for printing warnings, or data and regex dumping,
+not_a_number(), and so on.
+
+Requirements: should handle both byte and UTF8 strings. isPRINT()
+characters printed as-is, character less than 256 as \xHH, Unicode
+characters as \x{HHH}. Don't assume ASCII-like, either, get somebody
+on EBCDIC to test the output.
+
+Possible options, controlled by the flags:
+- whitespace (other than ' ' of isPRINT()) printed as-is
+- use isPRINT_LC() instead of isPRINT()
+- print control characters like this: "\cA"
+- print control characters like this: "^A"
+- non-PRINTables printed as '.' instead of \xHH
+- use \OOO instead of \xHH
+- use the C/Perl-metacharacters like \n, \t
+- have a maximum length for the produced string (read it from *lenp)
+- append a "..." to the produced string if the maximum length is exceeded
+- really fancy: print unicode characters as \N{...}
+
+NOTE: pv_display(), pv_uni_display(), sv_uni_display() are doing
+something like the above.
+
=head2 Overloadable regex assertions
This may or may not be possible with the current regular expression
algorithmically computed if you're dealing with Thai text. Hence, the
B<\b> assertion wants to be overloaded by a function.
-=head2 Unicode collation and normalization
+=head2 Unicode
-Simon Cozens promises to work on this.
+=over 4
- Collation? http://www.unicode.org/unicode/reports/tr10/
- Normalization? http://www.unicode.org/unicode/reports/tr15/
+=item *
-=head2 Unicode case mappings
+Allow for long form of the General Category Properties, e.g
+C<\p{IsOpenPunctuation}>, not just the abbreviated form, e.g.
+C<\p{IsPs}>.
+
+=item *
+
+Allow for the metaproperties: C<XID Start>, C<XID Continue>,
+C<NF*_NO>, C<NF*_MAYBE> (require the DerivedCoreProperties and
+DerviceNormalizationProperties files).
+
+There are also multiple value properties still unimplemented:
+C<Numeric Type>, C<East Asian Width>.
+
+=item *
Case Mappings? http://www.unicode.org/unicode/reports/tr21/
-=head2 Unicode regular expression character classes
+lc(), uc(), lcfirst(), and ucfirst() work only for some of the
+simplest cases, where the mapping goes from a single Unicode character
+to another single Unicode character. See lib/unicore/SpecCase.txt
+(and CaseFold.txt).
+
+=item *
-They have some tricks Perl doesn't yet implement.
+They have some tricks Perl doesn't yet implement like character
+class subtraction.
http://www.unicode.org/unicode/reports/tr18/
+=back
+
+See L<perlunicode/UNICODE REGULAR EXPRESSION SUPPORT LEVEL> for what's
+there and what's missing. Almost all of Levels 2 and 3 is missing,
+and as of 5.8.0 not even all of Level 1 is there.
+
=head2 use Thread for iThreads
Artur Bergman's C<iThreads> module is a start on this, but needs to
overhead of an XSUB; the user should be able to create PP code. Simon
Cozens has some ideas on this.
-=head2 spawnvp() on Win32
-
-Win32 has problems spawning processes, particularly when the arguments
-to the child process contain spaces, quotes or tab characters.
-
=head2 DLL Versioning
Windows needs a way to know what version of a XS or C<libperl> DLL it's
=head2 Cross compilation
Make Perl buildable with a cross-compiler. This will play havoc with
-Configure, which needs to how how the target system will respond to
+Configure, which needs to know how the target system will respond to
its tests; maybe C<microperl> will be a good starting point here.
(Indeed, Bart Schuller reports that he compiled up C<microperl> for
the Agenda PDA and it works fine.) A really big spanner in the works
target systems sees is not the same what the build host sees, various
input, output, and (Perl) library files need to be copied back and forth.
+As of 5.8.0 Configure mostly works for cross-compilation
+(used successfully for iPAQ Linux), miniperl gets built,
+but then building DynaLoader (and other extensions) fails
+since MakeMaker knows nothing of cross-compilation.
+(See INSTALL/Cross-compilation for the state of things.)
+
=head2 Perl preprocessor / macros
Source filters help with this, but do not get us all the way. For
=head2 All ARGV input should act like E<lt>E<gt>
+eg C<read(ARGV, ...)> doesn't currently read across multiple files.
+
=head2 Support for rerunning debugger
There should be a way of restarting the debugger on demand.
+=head2 Test Suite for the Debugger
+
+The debugger is a complex piece of software and fixing something
+here may inadvertently break something else over there. To tame
+this chaotic behaviour, a test suite is necessary.
+
=head2 my sub foo { }
The basic principle is sound, but there are problems with the semantics
This has been done in places, but needs a thorough code review.
Also fchdir is available in some platforms.
+=head2 Make v-strings overloaded objects
+
+Instead of having to guess whether a string is a v-string and thus
+needs to be displayed with %vd, make v-strings (readonly) objects
+(class "vstring"?) with a stringify overload.
+
=head1 Vague ideas
Ideas which have been discussed, and which may or may not happen.
It's unclear what this should do or how to do it without breaking old
code.
-=head2 Make tr/// return histogram
+=head2 Make tr/// return histogram of characters in list context
There is a patch for this, but it may require Unicodification.
=head2 "class"-based lexicals
Use flyweight objects, secure hashes or, dare I say it, pseudo-hashes instead.
+(Or whatever will replace pseudohashes in 5.10.)
=head2 byteperl
=head2 Lazy evaluation / tail recursion removal
-C<List::Util> in core gives some of these; tail recursion removal is
-done manually, with C<goto &whoami;>. (However, MJD has found that
-C<goto &whoami> introduces a performance penalty, so maybe there should
-be a way to do this after all: C<sub foo {START: ... goto START;> is
-better.)
+C<List::Util> gives first() (a short-circuiting grep); tail recursion
+removal is done manually, with C<goto &whoami;>. (However, MJD has
+found that C<goto &whoami> introduces a performance penalty, so maybe
+there should be a way to do this after all: C<sub foo {START: ... goto
+START;> is better.)
+
+=head2 Make "use utf8" the default
+
+Because of backward compatibility this is difficult: scripts could not
+contain B<any legacy eight-bit data> (like Latin-1) anymore, even in
+string literals or pod. Also would introduce a measurable slowdown of
+at least few percentages since all regular expression operations would
+be done in full UTF-8. But if you want to try this, add
+-DUSE_UTF8_SCRIPTS to your compilation flags.
+
+=head2 Unicode collation and normalization
+
+The Unicode::Collate and Unicode::Normalize modules
+by SADAHIRO Tomoyuki have been included since 5.8.0.
+
+ Collation? http://www.unicode.org/unicode/reports/tr10/
+ Normalization? http://www.unicode.org/unicode/reports/tr15/
+
+=head2 Create debugging macros
+
+Debugging macros (like printsv, dump) can make debugging perl inside a
+C debugger much easier. A good set for gdb comes with mod_perl.
+Something similar should be distributed with perl.
+
+The proper way to do this is to use and extend Devel::DebugInit.
+Devel::DebugInit also needs to be extended to support threads.
+
+See p5p archives for late May/early June 2001 for a recent discussion
+on this topic.
+
+=cut
projects / p5sagit/p5-mst-13.2.git / blobdiff