extra little type check on .. operator
improve error message
fix the warning for casts to unreified types
squash npe
don't check type constraints for UnknownType type args
squash unnecessary error message
allow a tuple to be spread across multiple params #518
type argument inference for #518
Issue #447: Introduce interface `Annotated`
analyse emptiness for comprehensions #544
another test for #544
fix typechecking of anonymous iterable arg in named param list
for #544, #465, #543
Remove x?[i] operator and clean up lexer
disallow mix of = and => for specifying a value
extra test
extra test to remind myself how *. and ?. work ;)
clean up a little
don't abbreviate Iterable type when type arg is a type parameter
lightly refactor and set Parameter of SpreadArgument
fix message