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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
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Serialization is the process of converting a data object—a combination of code and data represented within a region of data storage—into a series of bytes that saves the state of the object in an easily transmittable form.
Serialization in Java allows us to convert an Object to stream that we can send over the network or save it as file or store in DB for later usage. Deserialization is the process of converting Object stream to actual Java Object to be used in our program.
To serialize an object means to convert its state to a byte stream so way that the byte stream can be reverted back into a copy of the object. A Java object is serializable if its class or any of its superclasses implements either the java. io.
A non-serializable value is a complex object, like a class instance or a function. It is not an array, a plain serializable object, nor a primitive (like strings, numbers, booleans, null, etc.). Otherwise, it would be included in the list of the items that JSON supports.
No. There is no way to serialize a thunk in Haskell. Once code is compiled it is typically represented as assembly (for example, this is what GHC does) and there is no way to recover a serializable description of the function, let alone the function and environment that you'd like to make a thunk.
Yes. You could build custom solutions, such as describing and serializing a Haskell expression. Deserialization and execution could happen by way of interpretation (ex. Using the hint package).
Maybe. Someone (you?) could make a compiler or modify an existing compiler to maintain more information in a platform-agnostic manner such that things could be serialized without the user manually leveraging hint. I imaging this is an are under exploration by the Cloud Haskell (aka distributed-haskell) developers.
Why? I have also wanted an ability to serialize functions so that I could pass closures around in a flexible manner. Most of the time, though, that flexibility isn't actually needed and instead people want to pass certain types of computations that can be easily expressed as a custom data type and interpretation function.
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