1. The answer to your question: look at the Binary package (haskell libs) which implements a class Binary that allows binary IO, whether this package suffers from bit rot I don't know.
2. That haskell does not support a "Binary IO Standard" I believe to be an issue. An issue which with the advent of a "Standard FFI" is ripe to be addressed.
2.1. The binary package mentioned above implements it's own marshalling library which could to some extent(see 2.2.1) be subsumed by the FFI libraries.
2.2. The function of the Binary Class could be replaced by the Class Storable .ie. what is Storable can be written.
2.2.1 Notwithstanding the above, Class Binary may still be required. Haskell may opt for a "Standard Serialised" format across all platforms - this distinction comes into play with Big-endian vs little-endian int representations etc. Which for Storable does not come into play as by default you whish to have the same representation as the standard platform representation. Candidate representations could be ASN, XDR there are plenty of them (I believe that DCE, CORBA, Java etc all define some sort of standard serialisation).
2.2.1.1 There may be a need to define a set of data types similar to the CForeign package eg XDRInt etc, but on first inspection I believe them to be unnecessary.
2.2.2 A standard serialised binary representation would be of some benefit allowing sharing of binary files across platforms.
2.3 Class Storable or Binary could be made derivable, thereby facilitating the easy marshalling of structures to disk, see note below.
2.4 I guess it all comes down to whether the Haskell community feels that no standard binary io is ok.
deriving instances of Storable Wed, 05 Feb 2003 20:37:25 +1100
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Is there any merit in the idea of allowing instances of Storable to be derived in a similar fashion to Show, providing that constituents are of class Storable.
for instance
(Int, Int)
two Ints would be marshalled into consecutive memory locations in their order of declaration.
(Int,String)
an Int followed by a String
dealing with constructors ========================== data X = X1 Int | X2 deriving Storable data Y = Y1 | Y2 deriving Storable
three possible alternatives spring to mind
A) Indexing Constructors by position
X1 -> 0:Int X2 -> 1
where 0, 1 represent the constructor indexes ":" represents that the data items are physically contiguous "->" reads "marshalled as"
This has the disadvantage of being sensitive to the constructor order
B) using the constructor name as the index X1 -> X1:Int X2 -> X2
has the disadvantage of requiring a variable amount of memory for the tag.
C) some other hash on the constructor name ?
I would think that implementation would be fairly straight forward?
The benefits would be significant - automatic marshalling of structures.
uses: storing to disk, passing over network etc etc..
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