Generics...
MR K P SCHUPKE
k.schupke at imperial.ac.uk
Thu Feb 5 16:01:08 EST 2004
> Presumably not "replace all Ints by Floats"
I've thought about it some more, and I don't think its
possible to do what I want using generics... Ideally I would like
to achieve the following type transformation:
type SqlColumn a = String
type TypedExpr a = Int
the function would map SqlColumns to TypedExpr... The actual code
generates an integer from a sequence to "tag" each column, but for
the sake of simplicity, the following types would be sufficient:
type SqlColumn a = String
type TypedExpr a = String
So we take a tuple of any length and return exactly the same
tuple, but with the types changed:
project :: (SqlColumn a,SqlColumn b) -> (TypedExpr a,TypedExpr b)
project :: (SqlColumn a,SqlColumn b,SqlColumn c) -> (TypedExpr a,TypedExpr b,TypedExpr c)
What do you think?
Regards,
Keean Schupke.
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