Proposal: Make intersect(By) lazier and faster

Thomas Schilling nominolo at
Thu Sep 16 19:27:23 EDT 2010

+1 for proposal

On 16 September 2010 17:20, Bas van Dijk <v.dijk.bas at> wrote:

> Agreed, but my reason for proposing using 'filter' instead of using a
> list comprehension is that I find it more "denotational". However, I
> think that's a matter of taste.

Funny, I feel the opposite. ;)  Also, list comprehensions are usually
best if you want to increase the likely hood of fusion because the
desugaring is under GHC's control.

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