I had an error underlined by the parser, that a
class I was referring to does not exist.

Thus I've added the class.
But the parser still reports the error. Moreover
the message about missing class is followed by a
totally unrelated and false statements.
See the attached screenhot for details.

When I modified the affected file (added a space,
removed it and saved), the error dismissed.

It seems, that the parser does not know about
changes, that happen outside of the parsed file. I
hope, that this will be improved by the usage of
metadata repository.