Dubious features

[Akim Demaille]

In the course of splitting the scanner, so that we have a more
state-less scanner and therefore more freedom in the parser, there are
two "features" that I would like to discuss, because I don't think we
should keep them (as are).

- Adding a trailing semi-colon

  I think we should not.  I understand worries about backward
  compatibility, but I'm not sure there are really projects using this
  feature of Bison, because, as I already reported, I have mainly seen
  projects using Bison as a Yacc, in which case the semicolon is no
  longer added.  How about making a warning in 2.4, and removing the
  "feature" in the future?


- The "arbitrary C-code after %union".

  This should follow the same path IMHO.  Actually, I can't imagine
  anything but a simple id to be valid here, so I also propose to
  replace immediately the "arbitrary C-code after %union" by a simple
  id.  This is the last issue where we need some form of state in our
  grammar scanner.