[Haskell-cafe] Overcome type restrictions?

[Vincent Beffara]

> We have and error of infinite type for
> Prelude> :t ((\(h:t) -> h t) [head, last, head, last, head, last])
>
> Of course, head and tail are incompatible on type level...
>>
>> It seems like you need heterogenous collections[0]

Well the error pops up much earlier than that, see:

Prelude> :t (\(h:t) -> h t)

>>
>> Regards,
>> Henk-Jan van Tuyl
>>
>>
>> [0] http://www.haskell.org/haskellwiki/Heterogenous_collections
>>
>>
>> -- 
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>>
>>
>> http://Van.Tuyl.eu/
>> http://members.chello.nl/hjgtuyl/tourdemonad.html
>> Haskell programming
>> --
>>

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