instead of a closed set of languages. I also removed the offsets:
I simply use the current region to determine whether the
preprocessing directie starts at the beginning of a line. I also
removed scanning line indicators, to make the lexer simpler.
LexToken.mll: Moved the function [check_right_context] that
checks stylistic constraints from Lexer.mll to
LexToken.mll. While this triplicates code (as CameLIGO, PascaLIGO
and ReasonLIGO share the same constraints), the benefit is that
Lexer.mll becomes more generic and the signature for the TOKEN
module is simpler (no more exporting predicates, except for
EOF). In accordance with the change of the preprocessor, the
lexers and parsers for LIGO now depend on the kind of comments,
not a fixed set of syntaxes. This gives more versatility when
adding a new language: only the kinds of its comments are needed,
although Lexer.mll and Preproc.mll may have to be modified if
they do not already know the comment delimiters, for example line
comments starting with #.
****************************************************************
BUG: The exceptions coming from LexToken.mll when a stylistic
constraint is broken in [LexToken.check_right_context] are not
caught yet.
****************************************************************
Lexer.mll: I moved out as much as I could from the header into a
new module LexerLib. The aim is to make it easy to reuse as much
as possible of the lexer machinerie, when it cannot be used as
is.
* Reverted [pos.mli] to the previous signature, except [Pos.min]
that now takes a labelled parameter [file].
* Reverted [ParserAPI.ml] to the previous signature.
* Reexported [shor_error] in [ParserUnit].
* Changed the modules [LexToken] so that they export one function
to make attributes, the first, additional paramater being "[@"
or "[@@" (and invalid in PascaLIGO).
* Added support in all [ParserLog] for attributes (pretty-printings).
* Added AST nodes [Attr] and [AttrDecl] to PascaLIGO. The simplifier
takes care of hooking them with their respective declarations
or discarding them. (In the future, we should issue a warning for detached
attributes.)
* Duplicate variants in the same type declaration
* Duplicate parameter in the same function declaration
* Shadowing of predefined value in a declaration
I fixed the architecture for that support: ParserMain.ml is now where
those specific errors are handled, and they are produced by the
semantic actions of the parsers.
* 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).
