Tighten up attribute recognition during parsing

Now it should be possible to use `[]` for wildcard patterns, for example:

  foo = foo.[hit]xx

Note that a leading bracket expression will still be recognized as attributes
and escaping or quoting it will inhibit pattern matching. To resolve this case
we need to specify an empty attribute list:

  foo = [] [abc]-foo.cxx

0 files changed, 0 insertions, 0 deletions