- Give unary `-` and `not` the same precedence as in C++
- Add detail to parse error messages, and make the --trace flag also enable parser debug tracing
- Make any new shift-reduce conflicts into build errors
- Use `%precedence` rather than `%nonassoc` where possible, in order to catch more grammar bugs at build time
Slowly bringing this into line with Bison's C++ example parser
so we can use strong semantic values for symbols rather than
leaking pointers. First step is to thread a `ParseAndLexContext`
object through the whole syntactic analysis state, like the
example has. In the example, it's called `driver`.
Co-authored-by: Geoff Romer <gromer@google.com>