[Haskell-cafe] Memory-mapped arrays? (IArray interfaces, slices, and so on)

Jules Bean jules at jellybean.co.uk
Wed Nov 7 17:10:16 EST 2007

Joel Reymont wrote:
> Is there such a thing as memory-mapped arrays in GHC?

In principle, there could be an IArray instance to memory-mapped files.

(There could also be a mutable version, but just the IArray version 
would be useful).

I noticed just the other day that there are some 'obvious' IArray 
constructors missing. It ought, for example, be possible to build a new 
IArray from an old from a subset of the elements; a dimensional slice 
going from an (Int,Int,Int) indexed array to (Int,Int), or a stride 
taking 'one element in three' along each axis, etc.

Annoyingly, it doesn't seem to be straightforward to make your own 
instances of IArray, since the important methods aren't exported.

I think there is real scope for some expansion here.


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