We could add something like this to primitive. It has a generalization of
things like STRef, under the name MutVar.
On Wed, Feb 11, 2015 at 7:03 PM, David Feuer
The problem they solve is perhaps not as well known as it should be:
Code that frequently modifies an `STRef Int`, for example, will typically surprise the programmer by allocating a ton of memory. This happens because the reference holds a *boxed* Int. Code like
modifySTRef ref (+1)
will allocate a new Int box every time. To the best of my knowledge, GHC makes no attempt to figure out if this is actually necessary and do something about it. The Data.Ref.Unboxed module in the ArrayRef package attempts to address this, but it doesn't seem to get much visibility, and its code hasn't been touched since 2009. What can we do about this? _______________________________________________ Libraries mailing list Libraries@haskell.org http://www.haskell.org/mailman/listinfo/libraries