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Re: Reduce dictionary lookups using LIT ?

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Mark Wills wrote:
> But... Is your system so slow that you need this? Rhetorical.

It's a Rod Pemberton idea.  Assume it to be wrong in every way.  In this 
case, the lookup for names comes before the lookup for numbers, so if you 
find a name, you are done, the time for number conversion isn't necessary.  
However, if he has a linear search, and LIT (or maybe D# and H#, a they are 
used in some Forths to denote specific bases rather than having the base 
prefixes) is found pretty early, then there is a benefit.  However, as such  
word would be defined pretty early (needed all the time), it is unlikely 
that you gain something.

If you have lots of literals, a slow dictionary search, and your Forth words 
don't conflict with literals (they usually shouldn't, at least in decimal 
mode), you could turn the search around: First try to convert as literal, 
and if that fails, search.  This would give a benefit, as indentifying a 
number is pretty fast, and in the "many literals" case the search is 
completed when it's a literal.

With Gforth's development version, you can shuffle the recognizer stack to 
give it a try.  But Gforth has a fast dictionary lookup...

-- 
Bernd Paysan
"If you want it done right, you have to do it yourself"
http://bernd-paysan.de/

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Reduce dictionary lookups using LIT ? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-07-01 20:24 -0400
  Re: Reduce dictionary lookups using LIT ? "Elizabeth D. Rather" <erather@forth.com> - 2014-07-01 19:39 -1000
    Re: Reduce dictionary lookups using LIT ? bruce.mcfarling@gmail.com - 2014-07-02 10:30 -0700
      Re: Reduce dictionary lookups using LIT ? "Elizabeth D. Rather" <erather@forth.com> - 2014-07-02 08:53 -1000
      Re: Reduce dictionary lookups using LIT ? Mark Wills <markwills1970@gmail.com> - 2014-07-02 13:47 -0700
        Re: Reduce dictionary lookups using LIT ? BruceMcF <agila61@netscape.net> - 2014-07-02 19:45 -0700
          Re: Reduce dictionary lookups using LIT ? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-07-03 16:56 +0000
            Re: Reduce dictionary lookups using LIT ? bruce.mcfarling@gmail.com - 2014-07-03 10:34 -0700
  Re: Reduce dictionary lookups using LIT ? Mark Wills <markwills1970@gmail.com> - 2014-07-02 01:27 -0700
    Re: Reduce dictionary lookups using LIT ? Bernd Paysan <bernd.paysan@gmx.de> - 2014-07-02 17:11 +0200
      Re: Reduce dictionary lookups using LIT ? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-07-02 16:31 +0000
        Re: Reduce dictionary lookups using LIT ? Bernd Paysan <bernd.paysan@gmx.de> - 2014-07-02 20:32 +0200
      Re: Reduce dictionary lookups using LIT ? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-07-03 03:01 -0400
        Re: Reduce dictionary lookups using LIT ? "Elizabeth D. Rather" <erather@forth.com> - 2014-07-02 21:42 -1000
        Re: Reduce dictionary lookups using LIT ? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-07-03 16:05 +0000
    Re: Reduce dictionary lookups using LIT ? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-07-03 03:00 -0400
  Re: Reduce dictionary lookups using LIT ? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-07-02 09:35 +0000
    Re: Reduce dictionary lookups using LIT ? "Elizabeth D. Rather" <erather@forth.com> - 2014-07-02 06:51 -1000
  Re: Reduce dictionary lookups using LIT ? chitselb <chitselb@gmail.com> - 2014-07-02 14:30 -0700
    Re: Reduce dictionary lookups using LIT ? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-07-03 03:51 -0400
  Re: Reduce dictionary lookups using LIT ? Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2014-07-03 02:41 -0700
    Re: Reduce dictionary lookups using LIT ? "Alex McDonald" <blog@rivadpm.com> - 2014-07-03 11:44 +0100
      Re: Reduce dictionary lookups using LIT ? Stefan Mauerhofer <smauerhofer@androsoft.ch> - 2014-07-03 06:03 -0700
        Re: Reduce dictionary lookups using LIT ? "Alex McDonald" <blog@rivadpm.com> - 2014-07-03 15:16 +0100
          Re: Reduce dictionary lookups using LIT ? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-07-03 16:31 +0000
            Re: Reduce dictionary lookups using LIT ? "Alex McDonald" <blog@rivadpm.com> - 2014-07-03 19:58 +0100
              Re: Reduce dictionary lookups using LIT ? "Alex McDonald" <blog@rivadpm.com> - 2014-07-03 20:02 +0100

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