Created
March 23, 2010 18:05
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Calculate the Least Upper Bound of two types.
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| object test { | |
| case class L[A, B]() { | |
| def ToLub[AA >: A <: L, BB >: B <: L, L] = new { type LUB = L } | |
| } | |
| val intBoolLub = L[Int, Boolean].ToLub | |
| (1: AnyVal) : intBoolLub.LUB | |
| 1: intBoolLub.LUB | |
| true: intBoolLub.LUB | |
| 0L: intBoolLub.LUB | |
| // | |
| // "": intBoolLub.LUB | |
| } |
Is it possible to make it work without the slightly clumsy ToLub call (or rather, can you hide it)?
Same problem as here
akka/akka#19418
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The return type of apply is based on the inferred type arguments A=Any, B=Any, and L=Any, long before any fruit is passed it's way.