Proposal: Tidy up and export PSQ from base

Johan Tibell johan.tibell at
Sun May 1 10:26:52 CEST 2011

On Sat, Apr 30, 2011 at 3:10 AM, Edward Z. Yang <ezyang at> wrote:
> The new IO event manager implements a priority search queue internally.
> This is a kind of handy data structure; in particular, some algorithmic
> improvements in Hoopl would require a decent priority queue implementation.
> I propose that we move GHC.Event.PSQ to Data.PSQ, cleaning up the dependency
> on GHC.Event.Unique, and export it unconditionally (right now it is only
> available on non-Windows.)

I just wanted to note that the PSQ was made monomorphic for
performance reasons (about a 30% improvement) and I be hesitant to use
a more generic version in the event manager unless it performs close
to the current implementation.


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