[Haskell-cafe] Splitting a string into chunks

[Robert Dockins]

On Jan 13, 2006, at 4:35 PM, Jon Fairbairn wrote:

> On 2006-01-13 at 13:32PST Jared Updike wrote:
>> That works except it loses single newline characters.
>>
>> let s = "1234\n5678\n\nabcdefghijklmnopq\n\n,,.,.,."
>> Prelude> blocks s
>> ["12345678","abcdefghijklmnopq",",,.,.,."]
>
> Also the argument to groupBy ought to be some sort of
> equivalence relation.

Humm, still not reflexive.  You need xor.

> blocks = map unlines
>          . filter (all $ not . null)
>          . groupBy (\a b -> not (null b|| null a))
>          . lines
>
> ... but that suffers from the somewhat questionable
> properties of lines and unlines.
>
> -- Jón Fairbairn                              Jon.Fairbairn at  
> cl.cam.ac.uk
>
>
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Rob Dockins

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Laugh hard; it's a long way to the bank.
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