This decreases total testing time by over a minute on my old Mac Pro.
It probably has much less effect on systems with fewer cores, but shouldn't
be any worse there.
Swift SVN r22745
To limit user confusion when using conditional expressions of type Bool?, we've decided to remove the BooleanType (aka "LogicValue") conformance from optional types. (If users would like to use an expression of type Bool? as a conditional, they'll need to check against nil.)
Note: This change effectively regresses the "case is" pattern over types, since it currently demands a BooleanType conformance. I've filed rdar://problem/17791533 to track reinstating it if necessary.
Swift SVN r20637
Similar to nil-coalescing operators in other languages, this operator takes an optional on the left and a non-optional expression on the right, and if the optional is nil, evaluates the right side, otherwise returning the value from the optional itself. <rdar://problem/15247356>
Swift SVN r20593
This is motivated by <rdar://problem/17051606>.
This ends up renaming variables as well, which seems right for
consistency since we use "predicate" as variable name.
Swift SVN r19135
