[Haskell-cafe] Re: Float instance of 'read'

Brandon S. Allbery KF8NH allbery at ece.cmu.edu
Wed Sep 17 15:44:12 EDT 2008

On 2008 Sep 17, at 14:38, Aaron Denney wrote:
> On 2008-09-17, Mauricio <briqueabraque at yahoo.com> wrote:
>>> Localized reading should be somewhere else, perhaps related to  
>>> Locales.
>> No! If we had that, string from a program would not
>> be readable by some program running in other machine,
>> or other locale. As, actually, you describe below.
>> Show and Read are for programs reading, not for
>> user reading. That's a work for Pango :)
> While a thousands separator can improve readability, it's not strictly
> necessary.  OTOH, a decimal separator is necessary.  As the comma's  
> not
> usable, that leaves us with the decimal point, and no thousands  
> separator.
> Lo and behold, that's exactly what Haskell uses.

There are languages which ignore _ in numbers, allowing it to be used  
as a thousands separator if desired.  ghc currently parses "1_234" as  
<1:number> <_234:symbol> and I'm tempted to wonder if anything depends  
on it.

brandon s. allbery [solaris,freebsd,perl,pugs,haskell] allbery at kf8nh.com
system administrator [openafs,heimdal,too many hats] allbery at ece.cmu.edu
electrical and computer engineering, carnegie mellon university    KF8NH

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