Re: GDB/MI Output Syntax ambiguity

[Michael Chastain <mec dot gnu at mindspring dot com>]

It's been a while since I wrote a yacc grammar, but my inclination
would be to enhance the lexer and distinguish some new terminals:

  TOKEN-UPARROW
  TOKEN-STAR
  TOKEN-PLUS
  TOKEN-EQUALS

Then the grammar goes from LALR(2) to LALR(1), because
result-record can start with TOKEN-UPARROW, which is just
one symbol, rather than token "^", which is two symbols.
That ought to make it yacc-parseable.

That keeps the token numbers in the natural place.

With drow's rule:

 output     -> [token] ( out-of-band-record-1 [token] )* [ result-record ] "(gdb)" nl

This is also LALR(1), but the token symbol is not bundled with
the wrong out-of-band-record-1, so the tree-value-constructing
code gets a little skewed.

But I'm rusty on all this.