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Re: Make double numbers notation more strict

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albert@spenarnc.xs4all.nl wrote:
> In article <nnd$6d306c76$0159a1e5@5ebe29de058d18a5>,
>  <albert@spenarnc.xs4all.nl> wrote:
>>In article <116js4d$3le16$1@dont-email.me>,
>>Krishna Myneni  <krishna.myneni@ccreweb.org> wrote:
>>>On 8/24/26 11:17 PM, dxf wrote:
>>>> On 25/08/2026 11:51 am, Krishna Myneni wrote:
>>>>> On 8/24/26 8:10 PM, dxf wrote:
>>>>>> On 24/08/2026 9:36 pm, albert@spenarnc.xs4all.nl wrote:
>>>>>>> What does the Forth community think of the following:
>>>>>>>
>>>>>>> Now double numbers have to end with a '.' (c-notation).
>>>>>>> Double precision numbers loose significance in the 64 bit era.
>>>>>>> Time to de-emphasize this.
>>>>>>> ...
>>>>>>
>>>>>> Moore said that about 32-bit (and double operators) back in '89 and
>>>>>> still folks are finding uses.  Getting rid of doubles/input just to
>>>>>> support floating-point which isn't even forth's niche (RPN and all that)
>>>>>> ... seems so wrong.
>>>>>>
>>>>>
>>>>> 1) Which Forth systems are getting rid of double length integer input?
>>>>>
>>>>> I originally did not implement double length integer input in kForth
>>to avoid confusion with floating point. However, with the
>>standardization of base prefixes, and with recognizers (though they are
>>not needed for this), it became easy to implement an unambiguous form of
>>input for double length numbers, requiring a base prefix character and a
>>trailing decimal point e.g.
>>>>>
>>>>> #-170141183460469231731687303715884105728.
>>>>> $ffffffffffffffffffffffffffffffff.
>>>>> %10110001111011000101111.
>>>>
>>>> Interesting because ...
>>>>
>>>>    hex #23E1 decimal f. 230.  ok
>>>>
>>>> works on my system (but apparently not others)
>>>> ...
>>>
>>>How is your example above relevant to interpreting double length
>>>integers? What happens when you append a trailing decimal point to
>>>"#23E1"? Does your system still interpret it as a floating point number?
>>
>>My goals was severely restricted. In the absence of prefixes and a
>>E fields, make double numbers such that it cannot possible be
>>interpreted as an inexact ("floating point") number.
> 
> The next step on this road is to require explicit number prefixes
> for double precision integers and declare the rest obsolescent.
> So each number with a single decimal point or an
> exponent designator lacking a prefix is fp.
> 
> Fine with me.

Just a little comment: it is easy to input or output floating point
numbers in hexadecimal.  Advantage compared to decimal is that
input and output can be exact.  So hexadecimal prefix on floating
point numbers makes sense.  But to allow this one either needs
separate hex float prefix or some other syntactic way to
distinguish them from double integers.

-- 
                              Waldek Hebisch

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Make double numbers notation more strict albert@spenarnc.xs4all.nl - 2026-08-24 13:36 +0200
  Re: Make double numbers notation more strict anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-08-24 14:44 +0000
  Re: Make double numbers notation more strict Stephen Pelc <stephen@vfxforth.com> - 2026-08-24 16:57 +0000
  Re: Make double numbers notation more strict dxf <dxforth@gmail.com> - 2026-08-25 11:10 +1000
    Re: Make double numbers notation more strict Paul Rubin <no.email@nospam.invalid> - 2026-08-24 18:25 -0700
      Re: Make double numbers notation more strict dxf <dxforth@gmail.com> - 2026-08-25 14:44 +1000
    Re: Make double numbers notation more strict Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-08-24 20:51 -0500
      Re: Make double numbers notation more strict dxf <dxforth@gmail.com> - 2026-08-25 14:17 +1000
        Re: Make double numbers notation more strict Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-08-25 05:51 -0500
          Re: Make double numbers notation more strict dxf <dxforth@gmail.com> - 2026-08-25 21:20 +1000
            Re: Make double numbers notation more strict Krishna Myneni <krishna.myneni@ccreweb.org> - 2026-08-25 10:41 -0500
              Re: Make double numbers notation more strict dxf <dxforth@gmail.com> - 2026-08-26 13:51 +1000
          Re: Make double numbers notation more strict albert@spenarnc.xs4all.nl - 2026-08-26 11:54 +0200
            Re: Make double numbers notation more strict albert@spenarnc.xs4all.nl - 2026-08-26 12:00 +0200
              Re: Make double numbers notation more strict antispam@fricas.org (Waldek Hebisch) - 2026-08-26 14:39 +0000
                Re: Make double numbers notation more strict anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-08-26 15:28 +0000
                Re: Make double numbers notation more strict peter <peter.noreply@tin.it> - 2026-08-26 18:42 +0200
                Re: Make double numbers notation more strict anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2026-08-26 17:04 +0000
                Re: Make double numbers notation more strict albert@spenarnc.xs4all.nl - 2026-08-27 12:43 +0200
        Re: Make double numbers notation more strict Hans Bezemer <the.beez.speaks@gmail.com> - 2026-08-26 09:12 +0200
    Re: Make double numbers notation more strict Hans Bezemer <the.beez.speaks@gmail.com> - 2026-08-26 09:15 +0200
  Re: Make double numbers notation more strict Hans Bezemer <the.beez.speaks@gmail.com> - 2026-08-26 09:09 +0200
    Re: Make double numbers notation more strict albert@spenarnc.xs4all.nl - 2026-08-26 12:22 +0200
      Re: Make double numbers notation more strict Hans Bezemer <the.beez.speaks@gmail.com> - 2026-08-26 19:40 +0200

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