G'day all. On Sat, Jul 05, 2003 at 11:44:54PM -0400, Dimitry Golubovsky wrote:
What would be really nice to have is some sort of object input/output over network. Then, by sending a String, I would expect it to be recreated at the other end. And if the other end expects, say [Int] then an error would be detected.
Well there is already a binding for COM (which isn't portable, of course), a beta binding for CORBA, several XML libaries and a half-finished binding for ASN.1. Any of these would get you at least part of the way there. I think what you are asking for, though, is some equivalent of Java's serializable objects. I'm not convinced that producing yet another RPC protocol would be a useful thing, even if it was optimised for Haskell. It seems to me that adequately supporting the large number of existing standards (off the top of my head: DCOM, CORBA, XML-RPC, SOAP, .NET, ASN.1 and Sun RPC; no doubt I've missed a few) would be a far better use of effort. One thing which would be good was a more extensible "derives" keyword which lets you automatically derive code to marshall and demarshall for whatever RPC protocol you want. I'd love to be able to write: data SomeComplexType = Stuff MoreStuff EvenMoreStuff | AndSomeMore AdNauseam deriving( Asn1.Ber, Asn1.Xer, XmlRpc, DCom ) and have it automatically generate any interface definitions (IDL, ASN.1 specifications, whatever) suitable to hold the data type.
I haven't looked through the whole GHC runtime, and maybe something like this is already there, any clue is welcome.
The only built-in thing is Read/Show, which is functional, but slow, as its representation is textual. Cheers, Andrew Bromage