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

On 2008 Sep 17, at 14:38, Aaron Denney wrote:

On 2008-09-17, Mauricio wrote:

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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@kf8nh.com system administrator [openafs,heimdal,too many hats] allbery@ece.cmu.edu electrical and computer engineering, carnegie mellon university KF8NH