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Re: does VFX have the same bug as Gforth?

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Anton Ertl wrote:

> Bernd Paysan <bernd.paysan@gmx.de> writes:
>>The idea that it's my proposal is silly; I jumped late on this
>>smart COMPILE, bandwagon.  Win32Forth STC already had it, you made a
>>posting proposing that, and Stephen gave a talk at a EuroForth, and then I
>>was
>>convinced.  This is nothing new, this has been in VFX for ages (and with
>>"ages" I mean really right from start).  This is known to work with the 1
>>million lines of CCS, and it also works with the 500 lines of guru code in
>>BerndOOF.  There's very little which survives both tests, and BerndOOF is
>>actually of the class *you* think would fail.
> ...
>> We can ask Stephen, how much code breakage he
>>has observed.
> 
> As it turns out, no need to ask around, just in the thread next door
> <lt79f6$b0o$1@dont-email.me> we get to see breakage from VFX's
> "COMPILE,", and in the core of VFX as well:
> 
> : [cif] [COMPILE] IF ; IMMEDIATE
> Err# -22 ERR: Control structure mismatch.
>  -> : [cif] [COMPILE] IF ; IMMEDIATE
> 
> How does COMPILE, come into play?  Look here:
> 
> see [compile]
> [COMPILE] (is IMMEDIATE)
> ( 08058398    E897FFFFFF )            CALL      08058334        '
> ( 0805839D    E8EEE7FFFF )            CALL      08056B90        COMPILE,
> ( 080583A2    C3 )                    NEXT,
> ( 11 bytes, 3 instructions )

Yes, taking away immediacy of words you expect to be immediate is bound to 
cause problems with words like [COMPILE], which assume that the user knows 
whether the word is immediate or not (which is a bad idea).

That's why POSTPONE was invented.  I don't quite understand why [COMPILE] 
was left in the standard, it's impossible to use correctly given that the 
standard doesn't tell which words are immediate and which aren't (with a few 
exceptions).

If you look at the definition of [COMPILE] in Gforth, you see that there's 
an obvious way to fix [COMPILE] in VFX:

: [compile] ( compilation "name" -- ; run-time ? -- ? ) \ core-ext bracket-
compile
    comp' drop
    dup [ comp' exit drop ] literal = if
	execute \ EXIT has default compilation semantics, perform them
    else
	compile,
    then ; immediate

Yeah, there's a special casing for EXIT, because people using [COMPILE] will 
assume EXIT to be non-immediate, so we "cheat".  VFX should cheat the same 
way, and have a small case statement with all the words users expect to be 
immediate.  As [COMPILE] is there for legacy code, with a very well-defined 
expectation of what it should do (just look at the Forth-83 standard which 
words are marked immediate), it's doable.

So the assumption that [COMPILE] is something simple doesn't hold if you 
deviate from the Forth-83 or Forth-79 standard with respect to immediacy of 
certain words.

In effect, the way [COMPILE] is written renders the entire semantics stuff 
null and void: It means that there is a direct relation from the immediate 
and compile-only flag to the way the word's description is structured: no 
interpretation semantics: compile-only.  Non-default compilation semantics: 
immediate.  Default compilation semantics: non-immediate.  As Gforth mostly 
follows the fig-Forth model, this is true for Gforth (with the excepton of 
EXIT).

BTW: There's no use of [compile] as a standard word in the entire Gforth 
source code (the cross compiler's [compile] doesn't count, because it does 
something different: It works for forward references, while postpone doesn't 
and can't), which makes the word of dubious quality.

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

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does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-17 21:09 -0700
  Re: does VFX have the same bug as Gforth? Bee <forth@calcentral.com> - 2014-08-17 23:06 -0700
    Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-18 17:03 -0700
      Re: does VFX have the same bug as Gforth? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-08-18 22:19 -0400
      Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-19 09:14 +0000
        Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-08-19 15:23 +0200
          Re: does VFX have the same bug as Gforth? "Alex McDonald" <blog@rivadpm.com> - 2014-08-19 14:54 +0100
            Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-08-19 16:09 +0200
              Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-19 15:39 +0000
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-08-19 22:34 +0200
                Re: does VFX have the same bug as Gforth? "Alex McDonald" <blog@rivadpm.com> - 2014-08-19 23:29 +0100
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-08-20 23:06 +0200
                Re: does VFX have the same bug as Gforth? "Alex McDonald" <blog@rivadpm.com> - 2014-08-20 22:21 +0100
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-20 07:46 +0000
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-08-21 00:26 +0200
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-20 22:42 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-21 10:23 +0000
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-21 23:29 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-22 12:54 +0000
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-22 17:54 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-23 10:46 +0000
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-23 11:15 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-24 13:32 +0000
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-24 10:40 -0700
                Re: does VFX have the same bug as Gforth? Bee <forth@calcentral.com> - 2014-08-24 22:03 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-25 08:31 +0000
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-25 22:55 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-21 12:45 +0000
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-22 15:13 +0000
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-08-22 18:47 +0200
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-22 18:28 -0700
                Re: does VFX have the same bug as Gforth? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-08-23 04:44 -0400
                Re: does VFX have the same bug as Gforth? Coos Haak <chforth@hccnet.nl> - 2014-08-23 16:15 +0200
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-23 11:50 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-23 07:15 +0000
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-08-23 22:12 +0200
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-24 03:51 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-24 13:36 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-25 04:16 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-25 09:44 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-25 11:53 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 06:34 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 03:55 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 12:37 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 08:24 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 13:55 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 10:42 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 16:05 +0000
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-09-23 17:20 +0200
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-09-23 11:29 -0500
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-09-23 23:01 +0200
                Re: does VFX have the same bug as Gforth? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-08-25 15:59 +0000
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 06:23 +0000
                Re: does VFX have the same bug as Gforth? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-08-26 09:15 +0000
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 13:23 +0000
                Re: does VFX have the same bug as Gforth? Mark Wills <markwills1970@gmail.com> - 2014-08-26 01:41 -0700
                Re: does VFX have the same bug as Gforth? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-08-26 09:32 +0000
                Re: does VFX have the same bug as Gforth? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-08-26 09:43 +0000
                Re: does VFX have the same bug as Gforth? Mark Wills <markwills1970@gmail.com> - 2014-08-26 02:48 -0700
                Re: does VFX have the same bug as Gforth? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-08-26 11:58 +0000
                Re: does VFX have the same bug as Gforth? Mark Wills <markwills1970@gmail.com> - 2014-08-26 05:20 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 12:30 +0000
                Re: does VFX have the same bug as Gforth? stephenXXX@mpeforth.com (Stephen Pelc) - 2014-08-25 14:15 +0000
                Re: does VFX have the same bug as Gforth? Mark Wills <markwills1970@gmail.com> - 2014-08-25 07:44 -0700
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-25 14:37 +0000
                Re: does VFX have the same bug as Gforth? stephenXXX@mpeforth.com (Stephen Pelc) - 2014-08-25 15:14 +0000
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-25 15:33 +0000
                Re: does VFX have the same bug as Gforth? Mark Wills <markwills1970@gmail.com> - 2014-08-26 01:56 -0700
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 04:16 -0500
                Re: does VFX have the same bug as Gforth? Mark Wills <markwills1970@gmail.com> - 2014-08-26 02:24 -0700
                Re: does VFX have the same bug as Gforth? albert@spenarnc.xs4all.nl (Albert van der Horst) - 2014-08-26 09:36 +0000
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 13:40 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 08:57 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 12:52 +0000
                Re: does VFX have the same bug as Gforth? stephenXXX@mpeforth.com (Stephen Pelc) - 2014-08-26 14:14 +0000
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 14:36 +0000
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-09-23 17:40 +0200
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 10:53 -0500
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-09-23 17:36 +0200
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-25 12:02 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 06:42 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 04:08 -0500
                Re: does VFX have the same bug as Gforth? stephenXXX@mpeforth.com (Stephen Pelc) - 2014-08-26 10:37 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-26 08:30 -0500
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-28 08:47 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-29 13:03 +0000
                Re: does VFX have the same bug as Gforth? Andrew Haley <andrew29@littlepinkcloud.invalid> - 2014-08-29 09:16 -0500
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 13:06 +0000
                Re: does VFX have the same bug as Gforth? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-08-26 07:36 -0400
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-09-23 17:28 +0200
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-24 09:48 +0000
                Re: does VFX have the same bug as Gforth? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-08-24 15:55 -0400
                Re: does VFX have the same bug as Gforth? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-08-24 15:55 -0400
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-25 08:26 +0000
                Re: does VFX have the same bug as Gforth? "Rod Pemberton" <dont_use_email@xnothavet.cqm> - 2014-08-26 07:36 -0400
                Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-26 12:12 +0000
                Re: does VFX have the same bug as Gforth? Bernd Paysan <bernd.paysan@gmx.de> - 2014-09-23 17:45 +0200
                Re: does VFX have the same bug as Gforth? Mark Wills <markwills1970@gmail.com> - 2014-08-21 03:25 -0700
                Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-21 23:14 -0700
            Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-19 14:16 +0000
  Re: does VFX have the same bug as Gforth? Bee <forth@calcentral.com> - 2014-08-17 23:16 -0700
    Re: does VFX have the same bug as Gforth? anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2014-08-19 09:40 +0000
  Re: does VFX have the same bug as Gforth? Paul E Bennett <Paul_E.Bennett@topmail.co.uk> - 2014-08-18 09:16 +0100
  Re: does VFX have the same bug as Gforth? Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2014-08-18 09:32 +0100
    Re: does VFX have the same bug as Gforth? "Alex McDonald" <blog@rivadpm.com> - 2014-08-18 13:09 +0100
  Re: does VFX have the same bug as Gforth? stephenXXX@mpeforth.com (Stephen Pelc) - 2014-08-18 12:29 +0000
    Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-18 17:10 -0700
      Re: does VFX have the same bug as Gforth? Bee <forth@calcentral.com> - 2014-08-18 17:48 -0700
        Re: does VFX have the same bug as Gforth? hughaguilar96@yahoo.com - 2014-08-18 18:23 -0700
      Re: does VFX have the same bug as Gforth? Gerry Jackson <gerry@jackson9000.fsnet.co.uk> - 2014-08-19 13:55 +0100

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