bug in instance Read Int

Malcolm Wallace Malcolm.Wallace at cs.york.ac.uk
Mon May 31 06:23:55 EDT 2004


The Haskell'98 Report specifies that 'read'ing an Int should accept
only decimal notation

    instance Read Int where
        readsPrec p = readSigned readDec

(or near equivalent), yet ghc seems to read hexadecimal Ints.

    Prelude> show (Char.chr (read "0x2B" :: Int))
    "'+'"
    Prelude>

Ghc's behaviour seems entirely reasonable, but it does not conform
to the Report.  Should we regard this as a bug in the definition
therefore?  Is there an on-going errata list for the final Revised
Report?

Regards,
    Malcolm



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