Decimal Point vs. Decimal Comma

I know that roughly half the world uses a period to separate the 
fractional part of a number from the integer part.  Roughly half the 
world uses a comma for the same purpose.  But what about in computer 
languages?  A little research showed that Algol was specified to work 
with either.  Other computer languages seem to work primarily or 
exclusively with a period (point).

Are there any languages that support both formats without special 
programming?

-- 

Rick

rickman <gnuarm@gmail.com> writes:
>I know that roughly half the world uses a period to separate the 
>fractional part of a number from the integer part.  Roughly half the 
>world uses a comma for the same purpose.  But what about in computer 
>languages?  A little research showed that Algol was specified to work 
>with either.

Not really.  Algol 60 (not sure about 68) did not specify the concrete
representation of the lexemes.  So one compiler could accept 123.45
and a different compiler could accept 123,45 as concrete syntax of the
same number.  But the compilers would not necessarily accept the other
syntax.  A typical standardization cockup.

>Are there any languages that support both formats without special 
>programming?

Some Forth implementations do.  E.g., SwiftForth and bigForth:

                       ANS bigFORTH 386-Linux rev. 2.3.1

123.45 d. 12345  ok
123,45 d. 12345  ok

A very early version of Gforth also worked that way, but I removed
this feature, because it's more important to be able to get a useful
error message if you use "2,", but the Forth system does not define
it.  I have not missed this feature, and I come from the part of the
world that uses decimal comma.

- anton
-- 
M. Anton Ertl  http://www.complang.tuwien.ac.at/anton/home.html
comp.lang.forth FAQs: http://www.complang.tuwien.ac.at/forth/faq/toc.html
     New standard: http://www.forth200x.org/forth200x.html
   EuroForth 2015: http://www.rigwit.co.uk/EuroForth2015/

On Sat, 2 Apr 2016 17:49:07 -0400, rickman <gnuarm@gmail.com> wrote:

>I know that roughly half the world uses a period to separate the 
>fractional part of a number from the integer part.  Roughly half the 
>world uses a comma for the same purpose.  But what about in computer 
>languages?  A little research showed that Algol was specified to work 
>with either.  Other computer languages seem to work primarily or 
>exclusively with a period (point).
>
>Are there any languages that support both formats without special 
>programming?

In COBOL:
DECIMAL-POINT IS COMMA

On 4/3/2016 2:23 AM, Anton Ertl wrote:
> rickman <gnuarm@gmail.com> writes:
>> I know that roughly half the world uses a period to separate the
>> fractional part of a number from the integer part.  Roughly half the
>> world uses a comma for the same purpose.  But what about in computer
>> languages?  A little research showed that Algol was specified to work
>> with either.
>
> Not really.  Algol 60 (not sure about 68) did not specify the concrete
> representation of the lexemes.  So one compiler could accept 123.45
> and a different compiler could accept 123,45 as concrete syntax of the
> same number.  But the compilers would not necessarily accept the other
> syntax.  A typical standardization cockup.
>
>> Are there any languages that support both formats without special
>> programming?
>
> Some Forth implementations do.  E.g., SwiftForth and bigForth:
>
>                         ANS bigFORTH 386-Linux rev. 2.3.1
>
> 123.45 d. 12345  ok
> 123,45 d. 12345  ok
>
> A very early version of Gforth also worked that way, but I removed
> this feature, because it's more important to be able to get a useful
> error message if you use "2,", but the Forth system does not define
> it.  I have not missed this feature, and I come from the part of the
> world that uses decimal comma.

But neither of these are "correct".  I was talking about the radix point 
that separates the fraction from the integer portion of a number.

-- 

Rick

On 4/3/2016 2:23 AM, Anton Ertl wrote:
> rickman <gnuarm@gmail.com> writes:
>> I know that roughly half the world uses a period to separate the
>> fractional part of a number from the integer part.  Roughly half the
>> world uses a comma for the same purpose.  But what about in computer
>> languages?  A little research showed that Algol was specified to work
>> with either.
>
> Not really.  Algol 60 (not sure about 68) did not specify the concrete
> representation of the lexemes.  So one compiler could accept 123.45
> and a different compiler could accept 123,45 as concrete syntax of the
> same number.  But the compilers would not necessarily accept the other
> syntax.  A typical standardization cockup.
>
>> Are there any languages that support both formats without special
>> programming?
>
> Some Forth implementations do.  E.g., SwiftForth and bigForth:
>
>                         ANS bigFORTH 386-Linux rev. 2.3.1
>
> 123.45 d. 12345  ok
> 123,45 d. 12345  ok
>
> A very early version of Gforth also worked that way, but I removed
> this feature, because it's more important to be able to get a useful
> error message if you use "2,", but the Forth system does not define
> it.  I have not missed this feature, and I come from the part of the
> world that uses decimal comma.

But neither of these are "correct".  I was talking about the radix point 
that separates the fraction from the integer portion of a number.

-- 

Rick

In comp.arch.embedded rickman <gnuarm@gmail.com> wrote:
> Are there any languages that support both formats without special 
> programming?

        ENVIRONMENT DIVISION.
        CONFIGURATION SECTION.
            DECIMAL-POINT IS COMMA.

COBOL :)

-- 
Nils M Holm  < n m h @ t 3 x . o r g >  www.t3x.org

On Sat, 2 Apr 2016 17:49:07 -0400, rickman <gnuarm@gmail.com> wrote:

>I know that roughly half the world uses a period to separate the 
>fractional part of a number from the integer part.  Roughly half the 
>world uses a comma for the same purpose.  But what about in computer 
>languages?  A little research showed that Algol was specified to work 
>with either.  Other computer languages seem to work primarily or 
>exclusively with a period (point).
>
>Are there any languages that support both formats without special 
>programming?

If I understand correctly that you're asking about numeric literals in
program source, then I think the answer is COBOL and very possibly
nothing else.  

It's trivial to make a lexer accept either number format, but many
languages use commas as separators for, e.g., function arguments,
array and list elements, etc. ...  so also using commas as decimal
marks would cause problems.

Consider:     x = f( 1,9 );

Is that one argument or two?  Depends on number lexing.  Given a
particular lexing, one of the two possible parses is an error - but
which depends on the declaration of f().  This could be extremely
confusing to a programmer.  The only way around it is to also change
the argument separator, or to enforce that truly separate values be
separated by whitespace in addition to the separator.

Pretty much only the whitespace separated sexpr syntax of Lisp (and
Scheme) is immune to the parsing issue ... languages like ML and
Haskel, etc. don't necessarily need commas for function calls, but
they still do use them for other things.

I'm not aware of any language that specifically addresses this issue
regarding its source code - all that I am familar with simply use the
dot syntax for decimals.  Number formats often are addressed as locale
issues for I/O libraries, but not for program source.

Many compilers now allow Unicode in their source, but programmers
still are actively discouraged from using non-ASCII characters.  And
non-English speaking programmers almost are forced to program in
English for portability.  English is the lingua franca of programming.
There have been compilers designed specifically for certain locales,
but sans government mandate of their use, none has ever been very
successful.


Incidentally, I'm not sure what you saw re: Algol, but neither Algol
60 nor 68 permitted commas as decimal marks - both used the dot
syntax.  I don't have a reference for Algol 58, but all the Algols
used commas as argument and array separators, so they all would have
been susceptible to the parsing issue described above.  

YMMV,
George

rickman wrote:
> I know that roughly half the world uses a period to separate the
> fractional part of a number from the integer part. Roughly half the
> world uses a comma for the same purpose. But what about in computer
> languages? A little research showed that Algol was specified to work
> with either. Other computer languages seem to work primarily or
> exclusively with a period (point).
>
> Are there any languages that support both formats without special
> programming?
>
Maybe by modfying the read-table of Common Lisp.
But this might already be "special programming"
and I don't even know exactly if this is possible
(but I very much suppose so).

http://clhs.lisp.se/Body/02_.htm
--> http://clhs.lisp.se/Body/02_aa.htm

Am 02.04.2016 um 23:49 schrieb rickman:
> I know that roughly half the world uses a period to separate the
> fractional part of a number from the integer part.  Roughly half the
> world uses a comma for the same purpose.  But what about in computer
> languages?

In computer languages we have barely enough punctuation letters 
available as it is, to express all the necessary things without being 
overly verbose.  Wasting one on a luxury item like that would IMHO be 
unjustifiable.

Programs need to be able to handle localized formats on input and 
output, but not in the source itself.

On Sun, 3 Apr 2016 14:18:56 +0200, Hans-Bernhard Br�ker
<HBBroeker@t-online.de> wrote:

>Am 02.04.2016 um 23:49 schrieb rickman:
>> I know that roughly half the world uses a period to separate the
>> fractional part of a number from the integer part.  Roughly half the
>> world uses a comma for the same purpose.  But what about in computer
>> languages?
>
>In computer languages we have barely enough punctuation letters 
>available as it is, to express all the necessary things without being 
>overly verbose.  Wasting one on a luxury item like that would IMHO be 
>unjustifiable.

Some computer languages like COBOL and FORTRAN could be written with 6
bit codes (like FIELDDATA).
 
Unfortunately languages like C and Pascal used characters from ISO-686
character sets, including characters reserved for national variants.


>Programs need to be able to handle localized formats on input and 
>output, but not in the source itself.

What is the problem of using Latin-1 (ISO 8859-1) in a programming
language ?

In fact it would be a great thing, if you could use UTF-8 in
programming, e.g. Greek letters Alfa and Beta as program variables ?
No need to do any translitteration from any textbok variables.