Gergely Buday wrote:
is it possible to write in Ur a type definiton that expresses that
type myRecord = { MyField : int, MyOtherField : string,
and here come some identically typed fields,
1: $((First : option price, Second :
option price) ++ map option otherFields),
2: $((First : option price, Second :
option price) ++ map option otherFields)
...
n: $((First : option price, Second :
option price) ++ map option otherFields)
}
where n is not fixed at the time of the writing but depends on other
definitions?
I would do it as:
type copiedType = float (* fill something else in here *)
con copiedFields = [1, 2, 3] (* fill something else in here *)
type myRecord = $([MyField = int, MyOtherField = string] ++ mapU
copiedType copiedFields)
You could make this abstraction first-class as a type-level function,
but that would require including a disjointness obligation, which would
complicate use of such types.
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