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Re: Question on CHAR and [CHAR]

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Rod Pemberton wrote:

> "Ed" <nospam@invalid.com> wrote in message
> news:jjrggf$jp7$2@news-01.bur.connect.com.au...
>> [...]
>> Rod's mention of quoted characters ('A') in other languages
>> and his examples involving  CHAR [CHAR]  suggests to me
>> he probably intended to write:
>>
>>     : T [CHAR] 'A' . ;
>>
>> rather than
>>
>>     : T CHAR 'A' . ;
>>
>
> In this case, what I wrote was what I intended.  I didn't know that 'n'
> style syntax was entirely separate from CHAR for Forth.  Single quotes  
> are
> usually required to delimit a character in other languages.  In fact, I
> couldn't find mention of it in the spec's.  In other languages, you can't
> have a A or Z etc by itself and it be a character.  It must be 'A' or 'Z'
> etc delimited by single-quotes.  So, I took CHAR 'A' in a definition to
> place a character value for A on the stack.  However, as others replied,
> CHAR gets a character from the input stream to the stack and 'A' by  
> itself
> places a character value on the stack.

This is correct.  The 200x document introduced 'A' as a character literal
that will leave the ordinal value of A on the stack.  Thus,

   'A' is equivalent to [CHAR] A'

So,

   : T CHAR 'A' . ;
   T X . gives 65 88

The CHAR works on the next character from the input stream (X).

While the 2x document requires both an open and close quote, I have
implemented it as an abbreviation for [CHAR], so the closing quote is
optional.

With the introduction of the character literal, [CHAR] is no longer
required, it is retained for backward compatibility.

-- 
Peter Knaggs

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Thread

Question on CHAR and [CHAR] "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-11 06:10 -0400
  Re: Question on CHAR and [CHAR] Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-11 06:03 -0500
  Re: Question on CHAR and [CHAR] Coos Haak <chforth@hccnet.nl> - 2012-03-11 13:09 +0100
    Re: Question on CHAR and [CHAR] "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-12 19:43 -0400
      Re: Question on CHAR and [CHAR] "Elizabeth D. Rather" <erather@forth.com> - 2012-03-12 16:22 -1000
        Re: Question on CHAR and [CHAR] Mark Wills <markrobertwills@yahoo.co.uk> - 2012-03-13 03:23 -0700
        Re: Question on CHAR and [CHAR] Josh Grams <josh@qualdan.com> - 2012-03-13 12:51 +0000
  Re: Question on CHAR and [CHAR] Josh Grams <josh@qualdan.com> - 2012-03-11 17:11 +0000
    Re: Question on CHAR and [CHAR] Jean-Bernard Faucon <jb@nospam.com> - 2012-03-11 21:34 +0100
    Re: Question on CHAR and [CHAR] anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-12 10:45 +0000
  Re: Question on CHAR and [CHAR] BruceMcF <agila61@netscape.net> - 2012-03-11 13:57 -0700
  Re: Question on CHAR and [CHAR] "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-11 17:06 -0400
    Re: Question on CHAR and [CHAR] Josh Grams <josh@qualdan.com> - 2012-03-11 21:38 +0000
      Re: Question on CHAR and [CHAR] "Elizabeth D. Rather" <erather@forth.com> - 2012-03-11 14:12 -1000
    Re: Question on CHAR and [CHAR] BruceMcF <agila61@netscape.net> - 2012-03-11 18:42 -0700
    Re: Question on CHAR and [CHAR] Albert van der Horst <albert@spenarnc.xs4all.nl> - 2012-03-12 11:13 +0000
      Re: Question on CHAR and [CHAR] "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-12 19:46 -0400
        Re: Question on CHAR and [CHAR] "Elizabeth D. Rather" <erather@forth.com> - 2012-03-12 16:56 -1000
  Re: Question on CHAR and [CHAR] "Ed" <nospam@invalid.com> - 2012-03-14 16:35 +1100
    Re: Question on CHAR and [CHAR] Alex McDonald <blog@rivadpm.com> - 2012-03-14 08:49 -0700
      Re: Question on CHAR and [CHAR] "Ed" <nospam@invalid.com> - 2012-03-15 12:29 +1100
        Re: Question on CHAR and [CHAR] "Rod Pemberton" <do_not_have@noavailemail.cmm> - 2012-03-15 04:11 -0400
          Re: Question on CHAR and [CHAR] "Peter Knaggs" <pjk@bcs.org.uk> - 2012-03-15 10:24 +0000
            Re: Question on CHAR and [CHAR] Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-15 06:23 -0500
              Re: Question on CHAR and [CHAR] anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-15 12:05 +0000
                Re: Question on CHAR and [CHAR] Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-15 08:19 -0500
          Re: Question on CHAR and [CHAR] "Ed" <nospam@invalid.com> - 2012-03-17 13:17 +1100
            Re: Question on CHAR and [CHAR] anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-17 15:13 +0000
              Re: Question on CHAR and [CHAR] Andrew Haley <andrew29@littlepinkcloud.invalid> - 2012-03-18 06:07 -0500
              Re: Question on CHAR and [CHAR] "Ed" <nospam@invalid.com> - 2012-03-18 23:01 +1100
                Re: Question on CHAR and [CHAR] anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-18 15:21 +0000
                Re: Question on CHAR and [CHAR] Bernd Paysan <bernd.paysan@gmx.de> - 2012-03-18 23:15 +0100
        Re: Question on CHAR and [CHAR] anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2012-03-15 11:59 +0000
    Re: Question on CHAR and [CHAR] "Ed" <nospam@invalid.com> - 2012-03-15 12:29 +1100

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