Unfortunately, even thought all the front-ends use the same
ParserAPI.ml, that file cannot be moved to the folder `shared` due to
a dependency on AST.ml produced by Menhir.
* I added CLI option "--mono" to select the monolithic API of Menhir.
* I added a field "win" to the state of the lexer (a two-token
window for error reporting).
* I escaped LIGO strings before making them OCaml strings (for
example for printing).
I also had to remove the keywords [Down], [Fail] and [Step] in
PascaLIGO that made a mysterious and unwanted come back. (I did not
bother with [git blame]).
* [CameLIGO/ReasonLIGO] The AST node [EAnnot] (expressions
annotated by a type) now records the region in the source
code for the colon.
* [CameLIGO/ReasonLIGO/PascaLIGO] I added the syntax
%token <...> TOKEN "lexeme"
* [ReasonLIGO] I changed the AST nodes [Mtz] and [Str] to
[Mutez] and [String], respectively (in accordance with the
PascaLIGO front-end). I changed token [DOTDOTDOT] to
[ELLIPSIS].
* [ReasonLIGO] I added what was missing to make a loca build
with my Makefile.
