In Haskell, you can have infinite lists, because it doesn't completely compute them, it uses thunks. I am wondering if there is a way to serialize or otherwise save to a file a piece of data's thunk. For example let us say you have a list [0..]. Then you do some processing on it (I am mostly interested in tail and (:), but it should support doing filter or map as well.) Here is an example of sort of what I am looking for.
serial::(SerialThunk a)=>a->serThunk
serialized = serial ([0..] :: [Int])
main=writeToFile "foo.txt" serialized
And
deserial::(SerialThunk a)=>serThunk->a
main=do
deserialized <- readFromFile "foo.txt" :: IO [Int]
print $ take 10 deserialized
packman: "Evaluation-orthogonal serialisation of Haskell data, as a library" (thanks to a reddit link) -- is exactly what we have been looking for!
...this serialisation is orthogonal to evaluation: the argument is serialised in its current state of evaluation, it might be entirely unevaluated (a thunk) or only partially evaluated (containing thunks).
...The library enables sending and receiving data between different nodes of a distributed Haskell system. This is where the code originated: the Eden runtime system.
...Apart from this obvious application, the functionality can be used to optimise programs by memoisation (across different program runs), and to checkpoint program execution in selected places. Both uses are exemplified in the slide set linked above.
...Another limitation is that serialised data can only be used by the very same binary. This is however common for many approaches to distributed programming using functional languages.
...