[Haskell-cafe] ANNOUNCE: vector-bytestring-0.0.0.0

Bas van Dijk v.dijk.bas at gmail.com
Sat Oct 15 22:25:50 CEST 2011


On 15 October 2011 20:50, Ertugrul Soeylemez <es at ertes.de> wrote:
> Roman Leshchinskiy <rl at cse.unsw.edu.au> wrote:
>
>> > Personally, I think that ByteString and especially Vector Word8
>> > aren't strings and shouldn't be treated as such. But I wouldn't be
>> > strongly against showing them as strings. However, I *am* strongly
>> > against using UndecidableInstances in vector and I don't see how to
>> > implement this without using them.
>>
>> I meant OverlappingInstances, of course. To clarify, I would still
>> consider it if everybody thinks it's a really good idea.
>
> My suggestion was to remove the generic Show instance and add only
> specialized instances.  This is more work, but will also yield better
> results.  In particular, it allows specialized string representations
> for other types, too.

What exactly is the problem with using OverlappingInstances to define
specialized Show and Read instances for Vectors with certain element
types (Char, Word8, Bool)?

Am I missing something dangerous here?

Bas



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