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Always check out the latest perl5-porters discussions on these subjects
before embarking on an implementation tour.
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
Would be nice to have
pack "(stuff)*", "(stuff)?", "(stuff)+", "(stuff)4", ...
contiguous bitfields in pack/unpack
lexperl
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)
a way to make << and >> to shift bitvectors instead of numbers
Possible pragmas
debugger
optimize (use less qw[memory cpu])
Optimizations
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? (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
ref function in list context?
make tr/// return histogram in list context?
loop control on do{} et al
explicit switch statements
built-in globbing
compile to real threaded code
structured types
autocroak?
modifiable $1 et al
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