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()
+Requirements: should handle both byte and UTF-8 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.
Case Mappings? http://www.unicode.org/unicode/reports/tr21/
-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).
+Mostly implemented (all of 1:1, 1:N, N:1), only the "final sigma"
+and locale-specific rules of SpecCase are not implemented.
=item *
-They have some tricks Perl doesn't yet implement like character
-class subtraction.
+UTF-8 identifier names should probably be canonicalized: NFC?
- http://www.unicode.org/unicode/reports/tr18/
+=item *
+
+UTF-8 in package names and sub names? The first is problematic
+because of the mapping to pathnames, ditto for the second one if
+one does autosplitting, for example. Some of this works already
+in 5.8.0, but essentially it is unsupported. Constructs to consider,
+at the very least:
+
+ use utf8;
+ package UnicodePackage;
+ sub new { bless {}, shift };
+ sub UnicodeMethod1 { ... $_[0]->UnicodeMethod2(...) ... }
+ sub UnicodeMethod2 { ... } # in here caller(0) should contain Unicode
+ ...
+ package main;
+ my $x = UnicodePackage->new;
+ print ref $x, "\n"; # should be Unicode
+ $x->UnicodeMethod1(...);
+ my $y = UnicodeMethod3 UnicodePackage ...;
+
+In the above all I<UnicodeXxx> contain (identifier-worthy) characters
+beyond the code point 255, for example 256. Wherever package/class or
+subroutine names can be returned needs to be checked for Unicodeness.
=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.
+They have some tricks Perl doesn't yet implement, such as character
+class subtraction.
-=head2 use Thread for iThreads
+ http://www.unicode.org/unicode/reports/tr18/
-Artur Bergman's C<iThreads> module is a start on this, but needs to
-be more mature.
+=head2 Work out exit/die semantics for threads
-=head2 make perl_clone optionally clone ops
+There are some suggestions to use for example something like this:
+default to "(thread exiting first will) wait for the other threads
+until up to 60 seconds". Other possibilities:
-So that pseudoforking, mod_perl, iThreads and nvi will work properly
-(but not as efficiently) until the regex engine is fixed to be threadsafe.
+ use threads wait => 0;
-=head2 Work out exit/die semantics for threads
+Do not wait.
+
+ use threads wait_for => 10;
+
+Wait up to 10 seconds.
+
+ use threads wait_for => -1;
+
+Wait for ever.
+
+http://archive.develooper.com/perl5-porters@perl.org/msg79618.html
+
+=head2 Better support for nonpreemptive threading systems like GNU pth
+
+To better support nonpreemptive threading systems, perhaps some of the
+blocking functions internally in Perl should do a yield() before a
+blocking call. (Now certain threads tests ({basic,list,thread.t})
+simply do a yield() before they sleep() to give nonpreemptive thread
+implementations a chance).
+
+In some cases, like the GNU pth, which has replacement functions that
+are nonblocking (pth_select instead of select), maybe Perl should be
+using them instead when built for threading.
=head2 Typed lexicals for compiler
Locales and Unicode interact with each other in unpleasant ways.
One possible solution would be to adopt/support ICU:
- http://oss.software.ibm.com/developerworks/opensource/icu/project/
-
-=head2 Thread-safe regexes
-
-The regular expression engine is currently non-threadsafe.
+ http://oss.software.ibm.com/icu/index.html
=head2 Arithmetic on non-Arabic numerals
=head2 POSIX Unicode character classes
-(C<[=a=]> for equivalance classes, C<[.ch.]> for collation.)
+(C<[=a=]> for equivalence classes, C<[.ch.]> for collation.)
These are dependent on Unicode normalization and collation.
=head2 Factoring out common suffices/prefices in regexps (trie optimization)
=head2 Replace pod2html with something using Pod::Parser
The CPAN module C<Marek::Pod::Html> may be a more suitable basis for a
-C<pod2html> convertor; the current one duplicates the functionality
+C<pod2html> converter; the current one duplicates the functionality
abstracted in C<Pod::Parser>, which makes updating the POD language
difficult.
C<qr//> already gives us a way of saving compiled regexps, but it should
be done automatically.
-=head2 Re-entrant functions
-
-Add configure probes for C<_r> forms of system calls and fit them to the
-core. Unfortunately, calling conventions for these functions and not
-standardised.
-
=head2 Cross-compilation support
Bart Schuller reports that using C<microperl> and a cross-compiler, he
This should be allowed if the new keyset is a subset of the old
keyset. May require more extra code than we'd like in pp_aassign.
+=head2 Should overload be inheritable?
+
+Should overload be 'contagious' through @ISA so that derived classes
+would inherit their base classes' overload definitions? What to do
+in case of overload conflicts?
+
+=head2 Taint rethink
+
+Should taint be stopped from affecting control flow, if ($tainted)?
+Should tainted symbolic method calls and subref calls be stopped?
+(Look at Ruby's $SAFE levels for inspiration?)
+
+=head2 Perform correctly when XSUBs call subroutines that exit via goto(LABEL) and friends
+
+If an XSUB calls a subroutine that exits using goto(LABEL),
+last(LABEL) or next(LABEL), then the interpreter will very probably crash
+with a segfault because the execution resumes in the XSUB instead of
+never returning there.
+
=head1 Vague ideas
Ideas which have been discussed, and which may or may not happen.
The code we ship with Perl should look like good Perl 5.
+=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.
+
+=head2 truncate to the people
+
+One can emulate ftruncate() using F_FREESP and F_CHSIZ fcntls
+(see the UNIX FAQ for details). This needs to go somewhere near
+pp_sys.c:pp_truncate().
+
+One can emulate truncate() easily if one has ftruncate().
+This emulation should also go near pp_sys.pp_truncate().
+
+=head2 Unicode in Filenames
+
+chdir, chmod, chown, chroot, exec, glob, link, lstat, mkdir, open,
+opendir, qx, readdir, readlink, rename, rmdir, stat, symlink, sysopen,
+system, truncate, unlink, utime. All these could potentially accept
+Unicode filenames either as input or output (and in the case of system
+and qx Unicode in general, as input or output to/from the shell).
+Whether a filesystem - an operating system pair understands Unicode in
+filenames varies.
+
+Known combinations that have some level of understanding include
+Microsoft NTFS, Apple HFS+ (In Mac OS 9 and X) and Apple UFS (in Mac
+OS X), NFS v4 is rumored to be Unicode, and of course Plan 9. How to
+create Unicode filenames, what forms of Unicode are accepted and used
+(UCS-2, UTF-16, UTF-8), what (if any) is the normalization form used,
+and so on, varies. Finding the right level of interfacing to Perl
+requires some thought. Remember that an OS does not implicate a
+filesystem.
+
+(The Windows -C command flag "wide API support" has been at least
+temporarily retired in 5.8.1, and the -C has been repurposed, see
+L<perlrun>.)
+
+=head1 Unicode in %ENV
+
+Currently the %ENV entries are always byte strings.
+
=head1 Recently done things
These are things which have been on the todo lists in previous releases
Nick Ing-Simmons' C<perlio> supports an C<mmap> IO method.
-=head2 Byte to/from UTF8 and UTF8 to/from local conversion
+=head2 Byte to/from UTF-8 and UTF-8 to/from local conversion
C<Encode> provides this.
=head2 Bug tracking
-Richard Foley has written the bug tracking system at http://bugs.perl.org/
+Since 5.8.0 perl uses the RT bug tracking system from Jesse Vincent,
+implemented by Robert Spier at http://bugs.perl.org/
=head2 Integrate MacPerl
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.
-
-=head2 truncate to the people
-
-One can emulate ftruncate() using F_FREESP and F_CHSIZ fcntls
-(see the UNIX FAQ for details). This needs to go somewhere near
-pp_sys.c:pp_truncate().
-
-One can emulate truncate() easily if one has ftruncate().
-This emulation should also go near pp_sys.pp_truncate().
-
=head2 pack/unpack tutorial
Wolfgang Laun finished what Simon Cozens started.
https://perl5.git.perl.org / perl5.git / blobdiff