Cyrus Najmabadi b12be3db19 Remove dependency from the typechecker to the compiler host.
This also lets us not expose the compiler host from the Program instance.
The compiler host was only needed by the type checker to get the host newline.
The host newline was used for concatenating diagnostic message chains.  Now
we don't concatenate them up front.  Instead, we just store the message chain
in the diagnostic itself.  Then when we pass it to the host, it can then decide
what newline to use.
2015-02-04 23:20:26 -08:00
..