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Re: State and the standard ...

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Anton Ertl wrote:
> However, what I am worried about is that your approach breaks the
> currently existing relation between EXECUTE and COMPILE,.  Currently I
> know that, when I write some tool that processes xts in some way, I
> can COMPILE, these xts, and when they run, they will do what they
> would have done if I had EXECUTEd them right away.

Not really.  Consider you start with the state-smart world, and you compile 
in compilation state into a word that might later run in interpretation 
state.  If you EXECUTEd them right away, they would show their compilation 
semantics, if you COMPILE,d them, they would later show their interpretation 
semantics.  Or their compilation semantics, if the assumption above is 
wrong.

> Say, if I know that I want to EXECUTE a sequence of xts several times,
> I can define a colon definition, COMPILE, the xts into it, and then
> call the colon definition several times.  With your approach, I could
> no lonmger do that; you suggested that I should replace COMPILE, with
> POSTPONE LITERAL POSTPONE EXECUTE, but that's neither nice nor fast.

If you actually need that property.  For me, this looks like an academic 
exercise.  I've built my fair share of hand-written compilers.  They usually 
use the fragment Mitch Bradley posted to clarify what COMPILE, was for, i.e. 
that FIND 0> IF EXECUTE ELSE COMPILE, THEN, because they wanted the 
compilation semantics of the words found, not the interpretation semantics.  
This is the common case.  The fact that we need to look at a result from 
FIND, which is not passed on with the xt to decide whether to use EXECUTE or 
COMPILE, shows that this solution will have problems (and the problems are 
in the xt, which is why we can't find a good replacement for FIND).

The uncommon case, where you need this ['] foo execute style is where you 
deliberately want the interpretation semantics.  We don't actually have a 
POSTPONE compagnion for doing that, so I doubt it is of much use.  Rather 
the contrary: We do have POSTPONE, because this is what we want, and we 
don't want to distinguish between immediate and non-immediate words: We want 
compilation semantics.  POSTPONE is for named words, COMPILE, for xts, but 
because the immediate flag is lost when going to the xt, COMPILE, can't do 
its job properly.  IMHO that part of COMPILE,'s functionality you want is 
the one that is only there by accident - since STATE + IMMEDIATE are not a 
good way to have compilation macros.

BTW: for the state-smart implementations, it won't work either way.  
COMPILE, will just preserve the state-smart nature of the word, just as well 
as ]] LITERAL EXEUCTE [[ will (no difference there).

A typical hand-written compiler is e.g. the scoping and super call in an OOP 
package, which forces early binding, either to the particular class you 
selected, or to the super class.  You first look up the actual xt in the 
vtable (do the binding), and then what do you want with the token?  Compile 
it.  If it has special compilation semantics, you probably want it.

The only place in Gforth where the new semantics might case problems is in 
DEFERS.  DEFERS takes the action of a deferred word, and compiles it.  Note 
that a deferred word itself can only expose the execution semantics of the 
word bound to it, so the definition

: defers ( "name" -- ) ' defer@ compile, ; immediate compile-only

is actually not correct.  It should use that ]] literal execute [[ thing.  
The same thing for the OOP early binding, because the vtable also can only 
do EXECUTE, and therefore, COMPILE, would be wrong.

However, despite defers is used not so infrequently, this didn't cause any 
problem.

The most interesting piece here is probably porting BerndOOF to this 
approach, because in BerndOOF, you have methods with special compilation 
semantics.  But they aren't polymorph... though with the state-smart 
approach, that would have worked.

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

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State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-02-28 11:35 -0500
  Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-01 20:46 -0500
    Re: State and the standard ... Elizabeth D Rather <erather@forth.com> - 2013-03-01 19:33 -1000
    Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-02 03:33 -0600
      Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-03 18:09 -0500
        Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-03 15:01 -1000
        Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-04 03:06 -0600
        Re: State and the standard ... Lars Brinkhoff <lars.spam@nocrew.org> - 2013-03-04 11:38 +0100
  Re: State and the standard ... stephenXXX@mpeforth.com (Stephen Pelc) - 2013-03-02 11:34 +0000
    Re: State and the standard ... "A. K." <akk@nospam.org> - 2013-03-02 13:47 +0100
    Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-02 14:07 +0100
    Re: State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-03-02 12:38 -0500
      Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-02 15:50 -0600
        Re: State and the standard ... albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-02 22:11 +0000
          Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-03 02:51 +0100
            Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-03 14:56 +0000
              Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-03 22:42 +0100
                Re: State and the standard ... stephenXXX@mpeforth.com (Stephen Pelc) - 2013-03-03 22:02 +0000
                Re: State and the standard ... Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-04 00:19 -0800
                Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-05 00:14 +0100
                Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-08 16:34 +0000
                Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-07 18:04 +0000
                Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-08 01:31 +0100
                Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-08 14:41 +0000
                Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-09 17:04 +0100
                Re: State and the standard ... Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-08 02:19 -0800
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-08 04:25 -0600
                Re: State and the standard ... Mark Wills <markrobertwills@yahoo.co.uk> - 2013-03-08 03:35 -0800
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-08 06:58 -0600
                Re: State and the standard ... Coos Haak <chforth@hccnet.nl> - 2013-03-08 20:57 +0100
          Re: State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-03-03 11:25 -0500
            Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-03 15:13 -0600
              Re: State and the standard ... Coos Haak <chforth@hccnet.nl> - 2013-03-04 20:55 +0100
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-04 15:17 -0600
                Re: State and the standard ... Coos Haak <chforth@hccnet.nl> - 2013-03-05 00:27 +0100
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-04 18:41 -0600
                Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-04 20:49 -0500
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-05 02:59 -0600
                Re: State and the standard ... Alex McDonald <blog@rivadpm.com> - 2013-03-05 06:58 -0800
      Re: State and the standard ... Howerd <howerdo@yahoo.co.uk> - 2013-03-02 14:50 -0800
        Re: State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-03-03 11:06 -0500
      Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-03 14:17 +0000
    Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-02 17:55 +0000
      Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-02 20:24 +0100
        Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-03 14:25 +0000
        Re: State and the standard ... Lars Brinkhoff <lars.spam@nocrew.org> - 2013-03-03 16:27 +0100
          Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-03 15:15 -0600
            Re: State and the standard ... Howerd <howerdo@yahoo.co.uk> - 2013-03-03 13:41 -0800
              Re: State and the standard ... Paul Rubin <no.email@nospam.invalid> - 2013-03-10 00:51 -0800
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-10 04:35 -0500
                Re: State and the standard ... Paul Rubin <no.email@nospam.invalid> - 2013-03-10 20:56 -0700
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-11 03:47 -0500
                Re: State and the standard ... Paul Rubin <no.email@nospam.invalid> - 2013-03-13 23:48 -0700
                Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-13 21:01 -1000
                Re: State and the standard ... Paul Rubin <no.email@nospam.invalid> - 2013-03-14 00:23 -0700
                Re: State and the standard ... Lars Brinkhoff <lars.spam@nocrew.org> - 2013-03-14 09:18 +0100
                Re: State and the standard ... Lars Brinkhoff <lars.spam@nocrew.org> - 2013-11-21 14:26 +0100
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-14 03:34 -0500
                Re: State and the standard ... albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-14 11:25 +0000
                Re: State and the standard ... Mark Wills <forthfreak@gmail.com> - 2013-03-11 01:51 -0700
                Re: State and the standard ... Howerd <howerdo@yahoo.co.uk> - 2013-03-10 03:03 -0700
            Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-07 18:00 +0000
          Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-03 22:49 +0100
            Re: State and the standard ... "A. K." <akk@nospam.org> - 2013-03-05 00:18 +0100
              Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-04 18:44 -0600
          intelligent COMPILE, and smart COMPILE, anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-04 17:52 +0000
            Re: intelligent COMPILE, and smart COMPILE, Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-05 00:49 +0100
              Re: intelligent COMPILE, and smart COMPILE, stephenXXX@mpeforth.com (Stephen Pelc) - 2013-03-05 10:55 +0000
      Re: State and the standard ... albert@spenarnc.xs4all.nl (Albert van der Horst) - 2013-03-02 22:22 +0000
  Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-02 17:37 +0000
    Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2013-03-03 18:08 -0500
      Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-08 16:26 +0000
  Re: State and the standard ... Michael L Gassanenko <m_l_g3@yahoo.com> - 2013-03-04 23:08 -0800
    Re: State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-03-05 10:47 -0500
      Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-05 08:11 -1000
        Re: State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-03-05 13:44 -0500
          Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-05 09:26 -1000
            Re: State and the standard ... Michael L Gassanenko <m_l_g3@yahoo.com> - 2013-03-07 04:24 -0800
              Re: State and the standard ... Doug Hoffman <glidedog@gmail.com> - 2013-03-07 09:42 -0500
              Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-07 08:16 -1000
                Re: State and the standard ... anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2013-03-08 17:14 +0000
                Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-08 08:57 -1000
                Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-09 17:31 +0100
                Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-09 12:28 -0600
                Re: State and the standard ... Bernd Paysan <bernd.paysan@gmx.de> - 2013-03-09 21:41 +0100
          Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-06 17:51 -0500
            Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-06 13:13 -1000
        Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-06 17:51 -0500
          Re: State and the standard ... "Elizabeth D. Rather" <erather@forth.com> - 2013-03-06 13:12 -1000
      Re: State and the standard ... Andrew Haley <andrew29@littlepinkcloud.invalid> - 2013-03-05 18:18 -0600
        Re: State and the standard ... Brad Eckert <hwfwguy@gmail.com> - 2013-03-06 08:22 -0800
      Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-06 17:49 -0500
        Re: State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-03-06 17:56 -0500
        Re: State and the standard ... Rob Sciuk <rob@controlq.com> - 2013-03-06 18:17 -0500
          Re: State and the standard ... "Rod Pemberton" <do_not_have@notemailnotq.cpm> - 2013-03-08 04:22 -0500

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