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wish[1]  An efficient case selection structure would be nice, to avoid the
         overhead of long if-elseif...else-end constructs. I can do something
         similar (but not very efficient) now with:


         ...or with a table of functions which are used for their side-effects,
         but it would be hard for someone else reading the code to see what was
         happening; much better to localise the code at the point in the source
         where it is to be used.

         I presume it would be fairly easy for the compiler to plant a hidden
         jump table without requiring any new opcodes or anything.

         I'm not very bothered about having C's "fall-through" switch
         architecture, however. I'd happily give up typing 'break' at the
         end of cases and just accept an implicit and un-overrideable one.

         I don't really miss 'for' loops, but the above is an efficieny issue
         so I thought I'd raise it.

wish[2]  A hook into the raw uncompiled input before the lexer sees it, so I
         can use a regexp parser to add my own syntactic sugar for the "end
         user". I can see a use for this in providing meaningful operations
         on userdata, and it would fit in well with lua's policy regarding
         debugging: don't provide a pre-processor, just the hooks to allow
         one to be built.

Other minor things:

*  hex literals and bit-operators are useful if you are talking to hardware,
   but the operators would need a new fallback for the cases where casting
   a double to an int leads to loss of information (a 'range' fallback?).
   I've implemented the operators as functions (looks ugly) and patched
   "lex.c" manually to get the literals already, so _my_ vote goes to
   the form '#1234abcd' (case-insensitive), since that would give me
   *forwards* compatibility! ;-)

*  iolib lacks the converse of ascii(str), but it's trivial to write
   a C function for char(n).

That's just about all I can think of; I *like* the elegant terseness in
lua so I wouldn't want to see a great deal more...

Mark Ian Barlow                Non-Linear Control Consultants Ltd.
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