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Re: [ID 20010309.004] my-variables lose values while goto'ing within a for(;;)-loop
[perl5.git] / Todo
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1Always check out the latest perl5-porters discussions on these subjects
2before embarking on an implementation tour.
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4Bugs
5 remove recursion in regular expression engine
6 fix memory leaks during compile failures
7 make signal handling safe
8
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9Tie Modules
10 VecArray Implement array using vec()
11 SubstrArray Implement array using substr()
12 VirtualArray Implement array using a file
13 ShiftSplice Defines shift et al in terms of splice method
93a17b20 14
8990e307 15Would be nice to have
55f6b6ec 16 pack "(stuff)*", "(stuff)?", "(stuff)+", "(stuff)4", ...
54aff467 17 contiguous bitfields in pack/unpack
463ee0b2 18 lexperl
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19 bundled perl preprocessor/macro facility
20 this would solve many of the syntactic nice-to-haves
54aff467 21 use posix calls internally where possible
9cc29783 22 gettimeofday (possibly best left for a module?)
8990e307 23 format BOTTOM
2304df62 24 -i rename file only when successfully changed
54aff467 25 all ARGV input should act like <>
2304df62 26 report HANDLE [formats].
a0d0e21e 27 support in perlmain to rerun debugger
aa00cc68 28 regression tests using __DIE__ hook
aa00cc68 29 lexically scoped functions: my sub foo { ... }
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30 the basic concept is easy and sound,
31 the difficulties begin with self-referential
32 and mutually referential lexical subs: how to
33 declare the subs?
34 lexically scoped typeglobs? (lexical I/O handles work now)
55f6b6ec 35 wantlvalue? more generalized want()/caller()?
54aff467 36 named prototypes: sub foo ($foo, @bar) { ... } ?
7b8d334a 37 regression/sanity tests for suidperl
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38 iterators/lazy evaluation/continuations/first/
39 first_defined/short-circuiting grep/??
40 This is a very thorny and hotly debated subject,
54aff467 41 tread carefully and do your homework first
54aff467 42 generalise Errno way of extracting cpp symbols and use that in
55f6b6ec 43 Errno, Fcntl, POSIX (ExtUtils::CppSymbol?)
54aff467 44 the _r-problem: for all the {set,get,end}*() system database
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45 calls (and a couple more: readdir, *rand*, crypt, *time,
46 tmpnam) there are in many systems the _r versions
54aff467 47 to be used in re-entrant (=multithreaded) code
24e11b2a 48 Icky things: the _r API is not standardized and
54aff467 49 the _r-forms require per-thread data to store their state
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50 cross-compilation support
51 host vs target: compile in the host, get the executable to
52 the target, get the possible input files to the target,
53 execute in the target (and do not assume a UNIXish shell
54 in the target! e.g. no command redirection can be assumed),
55 get possible output files back to to host. this needs to work
56 both during Configure and during the build. You cannot assume
57 shared filesystems between the host and the target (you may need
58 e.g. ftp), executing the target executable may involve e.g. rsh
53c32ee0 59 a way to make << and >> to shift bitvectors instead of numbers
8990e307 60
a0d0e21e 61Possible pragmas
85e6fe83 62 debugger
54aff467 63 optimize (use less qw[memory cpu])
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64
65Optimizations
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66 constant function cache
67 switch structures
a0d0e21e 68 foreach(reverse...)
54aff467 69 cache eval tree (unless lexical outer scope used (mark in &compiling?))
463ee0b2 70 rcatmaybe
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71 shrink opcode tables via multiple implementations selected in peep
72 cache hash value? (Not a win, according to Guido)
73 optimize away @_ where possible
55f6b6ec 74 tail recursion removal
8990e307 75 "one pass" global destruction
54aff467 76 rewrite regexp parser for better integrated optimization
aa00cc68 77 LRU cache of regexp: foreach $pat (@pats) { foo() if /$pat/ }
463ee0b2 78
a0d0e21e 79Vague possibilities
54aff467 80 ref function in list context?
463ee0b2 81 make tr/// return histogram in list context?
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82 loop control on do{} et al
83 explicit switch statements
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84 built-in globbing
85 compile to real threaded code
86 structured types
85e6fe83 87 autocroak?
54aff467 88 modifiable $1 et al