-Must-have external packages
- POSIX
- X/Motif/whatever
+Always check out the latest perl5-porters discussions on these subjects
+before embarking on an implementation tour.
Bugs
- BEGIN { require 'perldb.pl' }
- Make yyparse recursion longjmp() proof.
- perl -c shell_script bug
- fix the need for double ^D on $x
- STDOUT->print("howdy\n");
- %ENV not there
- Make "delete $array{$key} while ($key) = each %array" safe
- using unpack(P,$ref) shouldn't unref the ref
- binary function is missing
- wrong line reported for runtime elsif condition error
- unreference variable warnings busted (but don't warn on $seen{$key}++)
+ remove recursion in regular expression engine
+ fix memory leaks during compile failures
+ make signal handling safe
-Regexp extensions
- /m for multiline
- /\Afoo/ (beginning of string, or where previous g match left off)
- /foo\Z/ (end of string only)
- negative regexp assertions?
- /<>/x for grouping?
- /f for fixed variable interpolation?
- Rewrite regexp parser for better integrated optimization
+Tie Modules
+ VecArray Implement array using vec()
+ SubstrArray Implement array using substr()
+ VirtualArray Implement array using a file
+ ShiftSplice Defines shift et al in terms of splice method
-Nice to have
- Profiler
- pack "(stuff)*"
+Would be nice to have
+ pack "(stuff)*", "(stuff)?", "(stuff)+", "(stuff)4", ...
+ contiguous bitfields in pack/unpack
lexperl
- Bundled perl preprocessor
- FILEHANDLE methods
- Make $[ compile-time instead of run-time
+ bundled perl preprocessor/macro facility
+ this would solve many of the syntactic nice-to-haves
+ use posix calls internally where possible
+ gettimeofday (possibly best left for a module?)
+ format BOTTOM
+ -i rename file only when successfully changed
+ all ARGV input should act like <>
+ report HANDLE [formats].
+ support in perlmain to rerun debugger
+ regression tests using __DIE__ hook
+ lexically scoped functions: my sub foo { ... }
+ the basic concept is easy and sound,
+ the difficulties begin with self-referential
+ and mutually referential lexical subs: how to
+ declare the subs?
+ lexically scoped typeglobs? (lexical I/O handles work now)
+ wantlvalue? more generalized want()/caller()?
+ named prototypes: sub foo ($foo, @bar) { ... } ?
+ regression/sanity tests for suidperl
+ iterators/lazy evaluation/continuations/first/
+ first_defined/short-circuiting grep/??
+ This is a very thorny and hotly debated subject,
+ tread carefully and do your homework first
+ generalise Errno way of extracting cpp symbols and use that in
+ Errno, Fcntl, POSIX (ExtUtils::CppSymbol?)
+ the _r-problem: for all the {set,get,end}*() system database
+ calls (and a couple more: readdir, *rand*, crypt, *time,
+ tmpnam) there are in many systems the _r versions
+ to be used in re-entrant (=multithreaded) code
+ Icky things: the _r API is not standardized and
+ the _r-forms require per-thread data to store their state
+ memory profiler: turn malloc.c:Perl_get_mstats() into
+ an extension (Devel::MProf?) that would return the malloc
+ stats in a nice Perl datastructure (also a simple interface
+ to return just the grand total would be good)
+ cross-compilation support
+ host vs target: compile in the host, get the executable to
+ the target, get the possible input files to the target,
+ execute in the target (and do not assume a UNIXish shell
+ in the target! e.g. no command redirection can be assumed),
+ get possible output files back to to host. this needs to work
+ both during Configure and during the build. You cannot assume
+ shared filesystems between the host and the target (you may need
+ e.g. ftp), executing the target executable may involve e.g. rsh
+ a way to make << and >> to shift bitvectors instead of numbers
+
+Possible pragmas
+ debugger
+ optimize (use less qw[memory cpu])
Optimizations
- Make specialized allocators
- Optimize switch statements
- Optimize foreach on array
- Optimize foreach (1..1000000)
- Set KEEP on constant split
- Cache eval tree (unless lexical outer scope used (mark in &compiling?))
+ constant function cache
+ switch structures
+ foreach(reverse...)
+ cache eval tree (unless lexical outer scope used (mark in &compiling?))
rcatmaybe
- Shrink opcode tables via multiple implementations selected in peep
- Cache hash value?
- Optimize away @_ where possible
- sfio?
-
-Need to think more about
- ref in list context
- When does split() go to @_?
- Figure out BEGIN { ... @ARGV ... }
- Implement eval once? (Unnecessary with cache?)
- Detect inconsistent linkage when using -DDEBUGGING?
- Populate %SIG at startup if appropriate
- Multiple levels of warning
+ shrink opcode tables via multiple implementations selected in peep
+ cache hash value? (Not a win, according to Guido)
+ optimize away @_ where possible
+ tail recursion removal
+ "one pass" global destruction
+ rewrite regexp parser for better integrated optimization
+ LRU cache of regexp: foreach $pat (@pats) { foo() if /$pat/ }
Vague possibilities
- readonly variables
- sub mysplice(@, $, $, ...)
- data prettyprint function? (or is it, as I suspect, a lib routine?)
- Nested destructors
+ ref function in list context?
make tr/// return histogram in list context?
- undef wantarray in void context
- goto &replacement_routine
- filehandle references
- Loop control on do{} et al
- Explicit switch statements
- perl to C translator
- multi-thread scheduling
+ loop control on do{} et al
+ explicit switch statements
built-in globbing
compile to real threaded code
structured types
+ autocroak?
+ modifiable $1 et al
projects / p5sagit/p5-mst-13.2.git / blobdiff