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Re: "comus" words

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"Alex McDonald" <blog@rivadpm.com> wrote in message
news:ec27bf9b-4983-4cc0-8297-930ab99835aa@l12g2000vbj.googlegroups.com...
> On Nov 28, 12:09 pm, "Rod Pemberton"
<do_not_h...@notemailnotz.cnm>
> wrote:
> > "Alex McDonald" <b...@rivadpm.com> wrote in message
>
news:670efa3a-4772-49c0-bfb9-90ac40de429a@g6g2000vbk.googlegroups.com...
> > > On Nov 27, 12:24 pm, "Rod Pemberton"
> > >  <do_not_h...@notemailnotz.cnm>> wrote:

[snip]

> > [ understanding of "may"]
>
> One simply needs to understand that "the car may crash"
> indicates that a crashed car is possible.

It also indicates that a never crashed car is a possible outcome
too.  I.e., there are two outcomes, not one, when one uses "may".

> "The number of characters in ccc may be zero to the number of
> characters in the parse area" indicates that zero characters is
> possible and valid. How hard is that?

That's not hard.  That's understood.  But, it also indicates that
an outcome where zero characters is never possible is valid too.
I.e., you're accepting one outcome of when "may" is used but
rejecting the other outcome.

> > Since you've now accepted Wikipedia's flaky definition as
> > valid, apparently, you re-read it and seriously try to
> > persuade me "zero is distinct from a null" as you've claimed.
> > As you said to me, please stop diverting. ;-)
> >
> > (Personally, I'm surprised you didn't argue against their
> > layman's definition... I would've. It sucks. I don't think
> > that's a very good definition at all.)
>
> Then please stop quoting material in which you have no faith
> in support of your argument.

First, this isn't about faith.

Second, I just asked if you were sure and cited something that
contradicted you.  Why you accepted that I agreed with what
someone else stated simply because it was cited by me is beyond
me...  It's not ludicrous to believe that someone can cite another
person, who has been proven false by history, without that
citation being a representation of that person's beliefs.  E.g.,
if you stated the world was round, I could cite Homer who thought
the world was flat, and ask if you're sure the world is round.  In
no way does that mean I believe the world is flat.

> > > > AIR, the definition of null or nothingness has three
> > > > different standard meanings, but only one is used
> > > > by programmers.
>
> > > Bollocks.
>
> > Bullshit? Really? I think your insults may apply to you...
>
> The word is not considered rude where I come from.

Ok.

> Translate it into American as "nuts". [link]

Then, improve this article.
http://en.wikipedia.org/wiki/Bollocks

> > In actuality, there are only two different _implementations_
> > of null listed by you above. They both have the same *meaning*
> > or definition: "empty" or "not valid".
>
> There are languages that support several types of "nulls".
> Assume X and Y;
>
> [snip]

All examples confuse implementation of null with a meaning for
null.  All cited demonstrate one meaning.  You'd have to check
some other industry or art, perhaps philosophy or religion instead
of programming, for the other meanings of null.

> > > > > Since 0 is a quantity, 0 ALLOT is acceptable; the zero
> > > > > refers to a quantity of address units, not
> > > > > "nothingness".
>
> > > > Zero isn't a quantity. Please give me zero apples. Once
> > > > you've done so, I expect to have some apples, not none.
> > > > Where are my apples? With zero, I won't have any apples.
> > > > I'd have none.  I.e., zero isn't a quantity. It's a
> > > > number.
>
> > > Contradicting your wikipedia sourced support.
>
> > Not true.
>
> I have a bag. In that bag there is one nut. I remove one nut.
> What quantity of nuts do I have in the bag?

There is no quantity of nuts in the bag ...

> I honestly can't believe how difficult you are making this.

See above.  It's in plain English.  So, ditto.

> > > > > In terms of RFC2119 (which postdates the Forth ANSI
> > > > > spec, so the ambiguity in that spec is forgivable) "MAY"
> > > > > is tightly defined, as is "SHALL". To use the language
> > > > > in that RFC to rewrite; "The number of characters in
> > > > > ccc shall be zero to the number of characters in the
> > > > > parse area".
>
> > > > RFC2119 is utterly irrelevant in regards to Forth ANSI
> > > > specification.
>
> > > [insult]
>
> > Despite the incorrect unsnipped statement above, RFC2119
> > supports my position ... If you knew that, why did you bring
> > it up?
>
> Either its irrelevant (your first statement) or it's relevant
> and it supports your position (second statement). Which
> is it?

Untrue.  It's both.  You've ignored the context of why it's both
irrelevant and supports my position.  It's irrelevant to ANS
specification since it has nothing whatsoever to do with it (first
statement).  It supports my position on what "may" means (second
statement).

> I prefer SHALL; but the ANS spec predates the RFC,
> and it is what it is.

Irrelevant.  Ed cited the ANS specification on "may".  It said the
same thing, albeit far more tersely.

> To get back to the point; S" " is a null string.

Is it a "null string"?  Please cite ANS as I don't see any
definition for a "null string".  FYI, "null" is only used four
times and none in regards to a string...  ANS Forth uses the term
"empty".  At best, ANS mentions a string of zero length, without
naming what it is...

> [S" "] has an address and length;

It's true that S" returns an address and length for valid
strings...

> the length is zero to indicate that there are no
> characters in the string.

Debatable, but it's definately good for safety and useability.

> C" " is a null counted string.

Is it a "null counted string"?  Please cite ANS as I don't see any
definition for a "null counted string" either.  FYI, "null" is
only used four times and none in regards to a string ...  ANS
Forth uses the term "empty".  At best, ANS mentions a string of
zero length, without naming what it is...


"counted string: A data structure consisting of one character
containing a length followed by zero or more contiguous data
characters. Normally, counted strings contain text."

As anyone can understand, the this definition allows for null
counted strings but doesn't require them.


3.1.3.4 Counted strings

"... between zero and the implementation-defined maximum
length for a counted string."

It's not clarified as to whether "between" as used here is
inclusive (very rare) of zero, or exclusive (common usage) of
zero.  The common exclusive meaning again supports the idea Forth
has no null strings.

> It has an address, and when
> COUNTed produces a null string. The spec says so.

That's not stated in 6.2.0855 for C".  It says to "parse".

"parse: To select and exclude a character string from the parse
area using a specified set of delimiting characters, called
delimiters."

"character string: Data space that is associated with a sequence
of consecutive character-aligned addresses.  Character strings
usually contain text.  Unless otherwise indicated, the term
"string" means "character string"."


As anyone can understand, the latter definition allows for null
strings but doesn't require them.


Of course 3.4.1 for Parsing of the text interpreter, says "may
be", which has two outcomes, i.e., one with null strings and one
without.

Elsewhere, in many places, the specification uses "zero or more".
Again, it allows for null strings, but doesn't require.

There is other "evidence" that null strings aren't supported in
ANS Forth such as TYPE conditionally emitting strings that aren't
null strings.  There is no need for conditionally emitting null
strings unless they don't exist in Forth.


For ANS Forth, WORD and PARSE and the optional
PARSE-WORD seem to be the only situations where
a string with zero length is required to be returned.


So, what you have is a specification where null strings - a term
which is never used nor defined - are optional at best everywhere,
has definitions which indicate that null strings aren't supported
by a number of words, and only has three Forth words that are
citable exceptions to that, since they require strings of zero
length, and even one of them is optional.


Rod Pemberton

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"comus" words "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-11-18 20:55 -0500
  Re: "comus" words "Elizabeth D. Rather" <erather@forth.com> - 2012-11-18 16:28 -1000
  Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-19 20:14 +1100
    Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-19 07:20 -0800
      Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-20 16:30 +1100
        Re: "comus" words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-20 10:22 +0000
          Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-22 01:59 +1100
            Re: "comus" words Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-11-21 09:34 -0600
            Re: "comus" words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-21 15:34 +0000
              Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-23 13:56 +1100
                Re: "comus" words "Elizabeth D. Rather" <erather@forth.com> - 2012-11-22 19:21 -1000
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-24 12:14 +1100
                Re: "comus" words "Elizabeth D. Rather" <erather@forth.com> - 2012-11-23 17:21 -1000
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-25 18:37 +1100
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-25 02:38 -0800
                Re: "comus" words Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-11-25 05:11 -0600
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-25 03:33 -0800
                Re: "comus" words Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-11-25 05:45 -0600
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-25 10:47 -0800
                Re: "comus" words Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-11-25 16:05 -0600
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-26 04:06 -0800
                Re: "comus" words albert@spenarnc.xs4all.nl (Albert van der Horst) - 2012-11-26 15:12 +0000
                Re: "comus" words "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-11-26 04:56 -0500
                Re: "comus" words Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-11-26 05:16 -0600
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-26 03:51 -0800
                Re: "comus" words "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-11-27 07:29 -0500
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-27 11:05 -0800
                Re: "comus" words "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-11-28 07:09 -0500
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-28 10:13 -0800
                Re: "comus" words "Rod Pemberton" <do_not_have@notemailnotz.cnm> - 2012-11-29 06:09 -0500
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-29 03:22 -0800
                Re: "comus" words Peter Knaggs <pjk@bcs.org.uk> - 2012-11-29 21:32 +0000
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-27 12:44 +1100
                Re: "comus" words Coos Haak <chforth@hccnet.nl> - 2012-11-27 17:59 +0100
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-29 12:53 +1100
                Re: "comus" words Coos Haak <chforth@hccnet.nl> - 2012-11-29 10:59 +0100
                Re: "comus" words Mark Wills <forthfreak@gmail.com> - 2012-11-29 02:22 -0800
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-29 02:58 -0800
                Re: "comus" words Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-11-29 05:53 -0600
                Re: "comus" words "Elizabeth D. Rather" <erather@forth.com> - 2012-11-29 09:38 -1000
                Re: "comus" words Andy Valencia <vandys@vsta.org> - 2012-11-29 13:10 +0000
                Re: "comus" words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-29 13:52 +0000
                Re: "comus" words Mark Wills <forthfreak@gmail.com> - 2012-11-29 06:09 -0800
                Re: "comus" words Andy Valencia <vandys@vsta.org> - 2012-11-29 15:43 +0000
                Re: "comus" words Coos Haak <chforth@hccnet.nl> - 2012-11-29 21:01 +0100
                Re: "comus" words Bernd Paysan <bernd.paysan@gmx.de> - 2012-11-29 23:17 +0100
                Re: "comus" words "Elizabeth D. Rather" <erather@forth.com> - 2012-11-29 17:01 -1000
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-30 08:30 +1100
                Re: "comus" words Coos Haak <chforth@hccnet.nl> - 2012-11-29 23:06 +0100
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-30 16:23 +1100
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-29 03:14 -0800
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-30 08:31 +1100
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-29 14:41 -0800
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-11-30 16:19 +1100
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-30 02:31 -0800
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-12-04 03:53 +1100
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-12-03 10:45 -0800
                Re: "comus" words "Ed" <invalid@nospam.com> - 2012-12-06 18:31 +1100
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-12-06 01:37 -0800
                Re: "comus" words albert@spenarnc.xs4all.nl (Albert van der Horst) - 2012-12-06 13:31 +0000
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-12-06 07:07 -0800
                Re: "comus" words "Elizabeth D. Rather" <erather@forth.com> - 2012-11-29 17:04 -1000
                Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-30 02:29 -0800
  Re: "comus" words Mark Wills <forthfreak@gmail.com> - 2012-11-19 05:33 -0800
  Re: "comus" words anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-11-19 14:45 +0000
  Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-19 07:43 -0800
    Re: "comus" words Alex McDonald <blog@rivadpm.com> - 2012-11-19 07:45 -0800
  Re: "comus" words oh2aun@gmail.com - 2012-11-22 21:10 -0800

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