-* Fixes
+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
-CC backend: goto, sort with non-default comparison. last for non-loop blocks.
-Version checking
-improve XSUB handling (both static and dynamic)
-sv_magic can do SvREFCNT_inc(obj) which messes up precalculated refcounts
-allocation of XPV[INAHC]V structures needs fixing: Perl tries to free
-them whereas the compiler expects them to be linked to a xpv[inahc]v_root
-list the same as X[IPR]V structures.
-ref counts
-perl_parse replacement
-fix cstring for long strings
-compile-time initialisation of AvARRAYs
-signed/unsigned problems with NV (and IV?) initialisation and elsewhere?
-CvOUTSIDE for ordinary subs
-DATA filehandle for standalone Bytecode program (easy)
-DATA filehandle for multiple bytecode-compiled modules (harder)
-DATA filehandle for C-compiled program (yet harder)
+Would be nice to have
+ pack "(stuff)*"
+ Contiguous bitfields in pack/unpack
+ lexperl
+ Bundled perl preprocessor
+ 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
+ reference to compiled regexp
+ lexically scoped functions: my sub foo { ... }
+ lvalue functions
+ regression/sanity tests for suidperl
+ Full 64 bit support (i.e. "long long"). Things to consider:
+ how to store/retrieve 32+ integers into/from Perl scalars?
+ 32+ constants in Perl code? (non-portable!)
+ 32+ arguments/return values to/from system calls? (seek et al)
+ 32+ bit ops (&|^~, currently explicitly disabled)
+ Generalise Errno way of extracting cpp symbols and use that in
+ Errno and Fcntl (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_dump_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.
-* Features
+Possible pragmas
+ debugger
+ optimize (use less memory, CPU)
-type checking
-compile time v. runtime initialisation
-save PMOPs in compiled form
-selection of what to dump
-options for cutting out line info etc.
-comment output
-shared constants
-module dependencies
+Optimizations
+ constant function cache
+ switch structures
+ foreach(reverse...)
+ Set KEEP on constant split
+ 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
+ "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
-* Optimisations
-collapse LISTOPs to UNOPs or BASEOPs
-compile-time qw(), constant subs
-global analysis of variables, type hints etc.
-demand-loaded bytecode (leader of each basic block replaced by an op
-which loads in bytecode for its block)
-fast sub calls for CC backend