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Re: A short history of the stages of development and status of RP's Forth interpreter.

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"Elizabeth D. Rather" <erather@forth.com> wrote in message
news:VZydnbeCxIolkRfSnZ2dnUVZ_rGdnZ2d@supernews.com...
> On 4/14/12 11:21 AM, Rod Pemberton wrote:
> > "Elizabeth D. Rather"<erather@forth.com>  wrote in message
> > news:NOqdnX8yHNVSgRrSnZ2dnUVZ_smdnZ2d@supernews.com...
...

> > FYI, this definition for SET won't work in a colon definition.  ANS' TO
> > which is used for VALUEs apparently does work in colon definitions, but
> > CONSTANT and VARIABLE don't.
>
> Of course not. This SET is a defining word, like CONSTANT and VARIABLE.
> Defining words are not used in definitions, they *are* definitions
> themselves ( : is one of many defining words).
>

Many other Forth words work for both interactively and in definitions.  So,
could they (CONSTANT, VARIABLE, etc.) be rewritten to do so?  From
what I've seen of other definitions, I think they could be.  I'd also think
that CONSTANTs inside definitions would be useful.

> Frankly, I don't understand the description of SET that you posted:
>
> SET        16b addr
>      A defining word executed in the form:
>             16b addr SET <name>
>      Defines a word <name> which, when executed, will cause the
>      value 16b to be stored at addr.
>
> If the point of SET is to define a word associated with an address that
> will store a given value in the address, why does the defining word take
> two arguments?

Bruce McFarland also thinks similarly.  Two fixed arguments is clearly least
useful (address and value both fixed).  One fixed argument is arguably more
useful (address fixed, takes value from stack).  Zero arguments is even more
useful (takes both from stack).  It's named ! (store).  However, as I
understand the syntax, the point is to define a word associated with both an
address and a value that will store the value at the address.  I.e., two
arguments, both fixed at the time SET is used.  (See Mark Wills post.)

Unless there is something I missed in the syntax or the definition to
indicate which arguments are fixed and which aren't, then my understanding
is valid even if it's not ...  Interpretation is a common problem with
abstracting syntax from implementation.  Everyone knows how something works
when the specification was written, but someone comes along later and says
or thinks: "That's not specified."  And, of course, it wasn't, and so they
did it differently ...  and maybe break code too ...

> > PS.  How does one text mark changes, like me inserting SET above when
> > [ ] are used for paraphrasing are also used in Forth notation?
>
> Sorry, don't understand the question.

If I insert text into another person's words to clarify them, English uses
brackets [ "inserted text" ] to mark those changes.  Forth also uses
brackets [ ] to indicate compiler mode changes and compiler words.  So, if I
inserted "I" into your last sentence:

> Sorry, [I] don't understand the question.

Does "[I]" mean "I" as in you or is it a Forth compile word [I] (bracket-I)?
This one is determinable from context.  [SET] didn't seem to be.

HTH,


Rod Pemberton

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Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-10 11:07 -0400
  Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-11 19:00 -0400
    Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-11 19:24 -0700
      Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-12 14:03 -0400
        Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-12 08:19 -1000
          Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-14 17:21 -0400
            Re: A short history of the stages of development and status of RP's Forth interpreter. Coos Haak <chforth@hccnet.nl> - 2012-04-15 00:11 +0200
            Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-14 13:48 -1000
              Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-15 13:09 -0400
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-15 08:06 -1000
                Re: A short history of the stages of development and status of RP's Forth interpreter. Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-04-16 09:45 +0000
                Re: A short history of the stages of development and status of RP's Forth interpreter. jacko <jackokring@gmail.com> - 2012-04-16 05:26 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-15 11:10 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-15 17:57 -0400
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-15 12:22 -1000
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-15 19:35 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-15 16:58 -1000
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-16 15:50 -0400
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-16 13:24 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-16 11:17 -1000
            Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-14 17:07 -0700
              Re: A short history of the stages of development and status of RP's Forth interpreter. Mark Wills <markrobertwills@yahoo.co.uk> - 2012-04-14 22:37 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-14 20:54 -1000
                Re: A short history of the stages of development and status of RP's Forth interpreter. Mark Wills <markrobertwills@yahoo.co.uk> - 2012-04-15 00:22 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-15 07:00 -0700
        Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-12 12:45 -0700
          Re: A short history of the stages of development and status of RP's Forth interpreter. Mark Wills <markrobertwills@yahoo.co.uk> - 2012-04-12 13:29 -0700
            Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-12 13:56 -0700
            Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-13 10:25 -0400
              Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-13 08:12 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-14 17:22 -0400
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-14 16:10 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-15 12:53 -0400
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-15 11:01 -0700
              Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-13 08:23 -0700
    Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-11 17:27 -1000
    Re: A short history of the stages of development and status of RP's Forth interpreter. Mark Wills <markrobertwills@yahoo.co.uk> - 2012-04-12 00:19 -0700
      Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-12 13:54 -0400
        Re: A short history of the stages of development and status of RP's Forth interpreter. Mark Wills <markrobertwills@yahoo.co.uk> - 2012-04-12 13:43 -0700
    Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-12 06:45 -0700
      Re: A short history of the stages of development and status of RP's  Forth interpreter. anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-04-12 15:01 +0000
        Re: A short history of the stages of development and status of RP's  Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-12 13:54 -0400
        Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-12 10:49 -0700
          Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-12 08:40 -1000
            Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-12 12:38 -0700
              Re: A short history of the stages of development and status of RP's Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-12 13:58 -1000
          Re: A short history of the stages of development and status of RP's  Forth interpreter. anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-04-13 10:42 +0000
            Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-13 08:34 -0700
              Re: A short history of the stages of development and status of RP's  Forth interpreter. anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-04-13 15:48 +0000
                Re: A short history of the stages of development and status of RP's  Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-13 08:25 -1000
                Re: A short history of the stages of development and status of RP's  Forth interpreter. stephenXXX@mpeforth.com (Stephen Pelc) - 2012-04-13 22:08 +0000
                Re: A short history of the stages of development and status of RP's  Forth interpreter. "Elizabeth D. Rather" <erather@forth.com> - 2012-04-13 12:26 -1000
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-13 16:14 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. jacko <jackokring@gmail.com> - 2012-04-14 09:04 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-14 15:59 -0700
                Re: A short history of the stages of development and status of RP's Forth interpreter. Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-04-15 10:50 +0000
                Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-15 07:06 -0700
                XT only or XT+NT (was: A short history ...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-04-14 14:06 +0000
                Re: XT only or XT+NT (was: A short history ...) Alex McDonald <blog@rivadpm.com> - 2012-04-16 02:39 -0700
            Re: A short history of the stages of development and status of RP's Forth interpreter. BruceMcF <agila61@netscape.net> - 2012-04-13 08:46 -0700
      Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-12 13:53 -0400
    Re: A short history of the stages of development and status of RP's Forth interpreter. "Rod Pemberton" <do_not_have@notemailnot.cmm> - 2012-04-19 17:06 -0400

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