+
+ -- For infix function defns, there should be only one infix *function*
+ -- (though there may be infix *datacons* involved too). So we don't
+ -- need fixity info to figure out which function is being defined.
+ -- a `K1` b `op` c `K2` d
+ -- must parse as
+ -- (a `K1` b) `op` (c `K2` d)
+ -- The renamer checks later that the precedences would yield such a parse.
+ --
+ -- There is a complication to deal with bang patterns.
+ --
+ -- ToDo: what about this?
+ -- x + 1 `op` y = ...
+