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Re: Stack Operator Symbols

From "HAA" <someone@microsoft.com>
Newsgroups comp.lang.forth
Subject Re: Stack Operator Symbols
Date 2016-10-31 13:11 +1100
Organization Aioe.org NNTP Server
Message-ID <nv6a7f$1nrm$1@gioia.aioe.org> (permalink)
References <4e481228-bd80-4e39-a629-90a690e50756@googlegroups.com><20161027191345.4f524e44@_> <-Lmdneii--uHXI_FnZ2dnUU7-VnNnZ2d@supernews.com><87d1ijmwc3.fsf@nightsong.com> <20161029184635.4cd709eb@_><87wpgqlfm9.fsf@nightsong.com> <ypidnaiGB-84P4jFnZ2dnUU7-UPNnZ2d@supernews.com>

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Elizabeth D. Rather wrote:
> On 10/29/16 4:45 PM, Paul Rubin wrote:
> > Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> writes:
> >> : 3DUP DUP 2OVER ROT ;
> >
> > Doh, I missed that one.  Nice.
> >
>
> This problem is in one of the introductory chapters of Forth
> Programmer's Handbook (see Amazon). The solution is posted online, but
> is a basic test of stack proficiency.
>
>
> Cheers,
> Elizabeth

What is in the introductory chapters of Forth Programmer's Handbook?
There's certainly no mention of 3DUP.

It's possible to estimate which stack sequence is going to deliver the better
performance.  Counting instructions is a good start.  The definition quoted
above comprises 3 instructions, as does the PICK version, so they're going
to be close (and they are).  Moving things to/from the return stack isn't cheap
so avoid it unless it's saving a lot of juggling on the data stack.

'common sense' strategies for choosing code work for all but the fanciest
code generators like Peter's where there's a lot going on 'behind your back'.
I personally would have a problem with a Forth compiler that removed the
programmer from the equation.


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Thread

Stack Operator Symbols trans <transfire@gmail.com> - 2016-10-24 20:42 -0700
  Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-25 01:58 -0700
  Re: Stack Operator Symbols november.nihal@gmail.com - 2016-10-25 10:52 -0700
  Re: Stack Operator Symbols Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2016-10-27 19:13 -0400
    Re: Stack Operator Symbols "Elizabeth D. Rather" <erather@forth.com> - 2016-10-27 17:08 -1000
      Re: Stack Operator Symbols "HAA" <someone@microsoft.com> - 2016-10-28 21:53 +1000
        Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-28 20:42 -0700
          Re: Stack Operator Symbols Walter Banks <walter@bytecraft.com> - 2016-10-29 17:15 -0400
            Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-29 17:27 -0700
        Re: Stack Operator Symbols "Elizabeth D. Rather" <erather@forth.com> - 2016-10-28 20:56 -1000
      Re: Stack Operator Symbols Paul Rubin <no.email@nospam.invalid> - 2016-10-29 00:46 -0700
        Re: Stack Operator Symbols Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-10-29 04:30 -0500
          Re: Stack Operator Symbols rickman <gnuarm@gmail.com> - 2016-10-29 16:58 -0400
          Re: Stack Operator Symbols Paul Rubin <no.email@nospam.invalid> - 2016-10-29 14:21 -0700
            Re: Stack Operator Symbols Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-10-30 04:03 -0500
              Re: Stack Operator Symbols Paul Rubin <no.email@nospam.invalid> - 2016-10-30 18:06 -0700
                Re: Stack Operator Symbols Spiros Bousbouras <spibou@gmail.com> - 2016-10-31 01:43 +0000
                Re: Stack Operator Symbols Paul Rubin <no.email@nospam.invalid> - 2016-10-30 19:23 -0700
                Re: Stack Operator Symbols Andrew Haley <andrew29@littlepinkcloud.invalid> - 2016-10-31 05:13 -0500
                Re: Stack Operator Symbols albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-10-31 12:42 +0100
                Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-31 12:12 +0000
                Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-31 14:49 +0000
                Re: Stack Operator Symbols mhx@iae.nl - 2016-10-31 13:17 -0700
                Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-11-03 16:38 +0000
                Re: Stack Operator Symbols Spiros Bousbouras <spibou@gmail.com> - 2016-11-20 14:33 +0000
                Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-31 08:35 +0000
            Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-30 11:01 +0000
              Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-30 10:01 -0700
            Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-11-03 14:46 -0700
              Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-11-04 23:04 +0000
                Re: Stack Operator Symbols Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2016-11-05 03:16 -0400
        Re: Stack Operator Symbols peter.m.falth@gmail.com - 2016-10-29 09:13 -0700
          Re: Stack Operator Symbols "HAA" <someone@microsoft.com> - 2016-10-30 08:47 +1100
            Re: Stack Operator Symbols trans <transfire@gmail.com> - 2016-10-29 14:57 -0700
              Re: Stack Operator Symbols "HAA" <someone@microsoft.com> - 2016-10-30 09:20 +1100
        Re: Stack Operator Symbols Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2016-10-29 18:46 -0400
          Re: Stack Operator Symbols Paul Rubin <no.email@nospam.invalid> - 2016-10-29 19:45 -0700
            Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-29 20:29 -0700
              Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-29 20:47 -0700
                Re: Stack Operator Symbols Cecil Bayona <cbayona@cbayona.com> - 2016-10-29 23:15 -0500
                Re: Stack Operator Symbols "Elizabeth D. Rather" <erather@forth.com> - 2016-10-29 21:37 -1000
                Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-30 10:07 -0700
            Re: Stack Operator Symbols "Elizabeth D. Rather" <erather@forth.com> - 2016-10-29 21:35 -1000
              Re: Stack Operator Symbols "HAA" <someone@microsoft.com> - 2016-10-31 13:11 +1100
                Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-30 20:02 -0700
                Re: Stack Operator Symbols "Elizabeth D. Rather" <erather@forth.com> - 2016-10-30 22:08 -1000
                Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-10-31 09:02 +0000
                Re: Stack Operator Symbols "HAA" <someone@microsoft.com> - 2016-11-03 20:49 +1100
                Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-11-03 15:33 +0000
                Re: Stack Operator Symbols Rod Pemberton <NeedNotReplyHere@xrsevnneqk.cem> - 2016-11-03 16:55 -0400
                Re: Stack Operator Symbols anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2016-11-03 22:21 +0000
  Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-27 20:31 -0700
    Re: Stack Operator Symbols november.nihal@gmail.com - 2016-10-28 09:52 -0700
      Re: Stack Operator Symbols hughaguilar96@gmail.com - 2016-10-28 20:32 -0700
  Re: Stack Operator Symbols Mark Wills <markwills1970@gmail.com> - 2016-10-30 04:49 -0700
    Re: Stack Operator Symbols Coos Haak <htrofhc@gmail.com> - 2016-10-30 14:49 +0100
      Re: Stack Operator Symbols Matthias Koch <matthias.koch@hot.uni-hannover.de> - 2016-10-31 13:31 +0100
        Re: Stack Operator Symbols Coos Haak <htrofhc@gmail.com> - 2016-10-31 14:12 +0100
          Re: Stack Operator Symbols Matthias Koch <matthias.koch@hot.uni-hannover.de> - 2016-10-31 15:03 +0100
        Re: Stack Operator Symbols Mark Wills <markwills1970@gmail.com> - 2016-11-03 14:22 -0700
          Re: Stack Operator Symbols Coos Haak <htrofhc@gmail.com> - 2016-11-04 00:46 +0100
        Re: Stack Operator Symbols "HAA" <someone@microsoft.com> - 2016-11-05 13:14 +1100
    Re: Stack Operator Symbols trans <transfire@gmail.com> - 2016-10-30 06:50 -0700
      Re: Stack Operator Symbols trans <transfire@gmail.com> - 2016-10-30 08:56 -0700
      Re: Stack Operator Symbols albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2016-10-30 18:19 +0100

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