- We switch to a model where let properties may be "initialized", but never
reassigned. Specifically, immutable properties in structs/classes may have
an init value specified in their declaration (but can then never be reset
in any init implementation) or not (in which case they must be initialized
exactly once on all paths through every init. This makes a lot more sense
for immutability, defines several problems away, and provides a path to
supporting things like (rdar://16181314)
- We now *never* default initialize an immutable property. Formerly
we would default initialize optional let properties to nil, but this
isn't actually useful, and allows an error of omission with let
properties.
This resolves: <rdar://problem/19035287> let properties should only be initializable, not reassignable
and possibly other radars.
Swift SVN r23779
