Groups | Search | Server Info | Keyboard shortcuts | Login | Register [http] [https] [nntp] [nntps]

Groups > comp.lang.forth > #59722

Re: FP-Number Ambiguities

Show all headers | View raw

In article <33aae2b8-f7c7-41e5-a790-88bcfb963372@googlegroups.com>,
 <minforth@arcor.de> wrote:
>Am Montag, 22. Mai 2017 13:56:42 UTC+2 schrieb Anton Ertl:
>> minforth@arcor.de writes:
>> >Am Sonntag, 21. Mai 2017 17:13:15 UTC+2 schrieb Anton Ertl:
>> >> minforth@arcor.de writes:
>> >> >well-behaving to legacy code
>> >>
>> >> If I load a legacy program containing "1.03" on a system with
>> >> CORE+DOUBLE+FLOAT, the program gets a float, while it expects a
>> >> double.  I.e., not at all well-behaved.
>> >>
>> >
>> >The standard 8.3.1 speaks only of the trailing decimal point, so 1.03
>> >is not strictly a double number.
>>
>> The standard has no say on legacy programs.  That's why they are
>> called legacy programs, not standard programs.
>>
>
>LOL !!
>
>> >I know that older "dinosaaur" Forths treated 1.03 as double number.
>>
>> Popular current Forth systems are "dinosaur" Forths in your
>> terminology:
>>
>
>Yes, pardon my terminology to make things mor pregnant.
>
>So popular Forths follow either "legacy" or "standard" as their particular
>authors like or do not like.
>
>Okay.......

Not okay. Upwards compatibility is not the same as "following legacy".

>
>
>> >To leave 0. "in the blue" as you suggested is nonsense (pardon me).
>>
>> It's the only good way I see to getting to the situation that you
>> claim is common sense.  Having "0." as double, and "1.03" as float is
>> even more confusing than having both as double.
>
>
>That's why I suggested that whenever the float wordset is loaded, it should
>overrule the legacy double number recognition.

Which is rejected by Anton Ertl and for a good reason. It is no problem
that after loading the float wordset more literals (denotations) are
accepted than before. It is bad if they change meaning.

>
>But you are right, it can be confusing when a user is unaware.

An understatement.

>
>Indeed the most consistent way would be to declare legacy double number
>recognition obsolete, unless they are casted by some prefix
>(# or [D] perhaps).
>

My preference is . Two dots in a word can never mean floating point.
And we already have dedicated the dot to double numbers.
******************************************
*    .1999.                              *
******************************************

Groetjes Albert.
-- 
Albert van der Horst, UTRECHT,THE NETHERLANDS
Economic growth -- being exponential -- ultimately falters.
albert@spe&ar&c.xs4all.nl &=n http://home.hccnet.nl/a.w.m.van.der.horst

Back to comp.lang.forth | Previous | Next — Previous in thread | Next in thread | Find similar | Unroll thread

Thread

FP-Number Ambiguities minforth@arcor.de - 2017-05-19 14:06 -0700
  Re: FP-Number Ambiguities anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-20 10:56 +0000
    Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-20 11:50 -0700
      Re: FP-Number Ambiguities anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-21 14:59 +0000
        Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-21 12:08 -0700
          Re: FP-Number Ambiguities mhx@iae.nl - 2017-05-21 12:50 -0700
            Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-21 15:04 -0700
          Re: FP-Number Ambiguities anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-22 11:43 +0000
            Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-22 06:40 -0700
              Re: FP-Number Ambiguities albert@cherry.spenarnc.xs4all.nl (Albert van der Horst) - 2017-05-22 16:33 +0200
                Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-22 08:34 -0700
              Double numbers and floats in the text interpreter (was: FP-Number...) anton@mips.complang.tuwien.ac.at (Anton Ertl) - 2017-05-22 16:17 +0000
    Re: FP-Number Ambiguities pahihu <pahihu@gmail.com> - 2017-05-24 10:19 -0700
      Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-24 11:21 -0700
        Re: FP-Number Ambiguities pahihu <pahihu@gmail.com> - 2017-05-24 12:13 -0700
          Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-24 13:12 -0700
  Re: FP-Number Ambiguities (answer imported from future) Jan Coombs <jenfhaomndgfwutc@murmic.plus.com> - 2017-05-20 22:54 +0100
  Re: FP-Number Ambiguities "HAA" <someone@microsoft.com> - 2017-05-24 17:21 +1000
    Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-24 01:11 -0700
      Re: FP-Number Ambiguities "HAA" <someone@microsoft.com> - 2017-05-25 12:28 +1000
        Re: FP-Number Ambiguities minforth@arcor.de - 2017-05-25 00:36 -0700

csiph-web