smolkaj / nice-parser Goto Github PK

Hello, I found this project very helpful as I tried to figure out how to use sedlex.

I think people might benefit from seeing an example in dune, especially since RWO is using it now.

(Related: #2; is this the described “hack?”)

So, I'm relatively new to OCaml (hence using this project to try and understand parsing in OCaml! 🤣); but I don't understand why CPP-style source-transformation is necessary to reach Menhir's generated “token definitions”:

#include "Tokens.ml"
  [@@deriving show, enumerate]

module Sedlexing = LexBuffer
open LexBuffer
(* ... so on, so forth ... *)

Can't we use some sort of built-in language mechanic to include the symbols from the generated Tokens module into both Lexer.mli and the (eventual) Lexer.ml?

This has been a show-stopper for me; as a newbie, I still really depend on Merlin to understand what's going on and write code — and the CPPO invocation at the top of these files completely breaks Merlin, right now. But if there's no other way to do this … )'=

(It looks like somebody's trying to build support for it, ocaml/merlin#548, but that may be a long way off? I'm kinda an outsider, so I'm not sure. See also: let-def/merlin-extend#7.)

Hi,

i get Error: Uninterpreted extension 'sedlex.regexp' as seen below. menhir is version 20180703.

Any idea how to fix this?

Thanks,
Lacramioara

====

isar:07:06:16:~/ocaml-parsing$ make
time -p jbuilder build @install
ocamlopt src/.ocaml_parsing.objs/ocaml_parsing__Lexer.{cmx,o} (exit 2)
(cd _build/default && /home/eugen/.opam/4.06.0/bin/ocamlopt.opt -w -40 -g -I src/.ocaml_parsing.objs -I /home/eugen/.opam/4.06.0/lib/base -I /home/eugen/.opam/4.06.0/lib/base/caml -I /home/eugen/.opam/4.06.0/lib/base/shadow_stdlib -I /home/eugen/.opam/4.06.0/lib/bytes -I /home/eugen/.opam/4.06.0/lib/gen -I /home/eugen/.opam/4.06.0/lib/menhirLib -I /home/eugen/.opam/4.06.0/lib/ocaml/compiler-libs -I /home/eugen/.opam/4.06.0/lib/ppx_deriving -I /home/eugen/.opam/4.06.0/lib/result -I /home/eugen/.opam/4.06.0/lib/sedlex -I /home/eugen/.opam/4.06.0/lib/sexplib0 -I /home/eugen/.opam/4.06.0/lib/stdio -intf-suffix .ml -no-alias-deps -open Ocaml_parsing -o src/.ocaml_parsing.objs/ocaml_parsing__Lexer.cmx -c -impl src/Lexer.pp.ml)
File "src/Lexer.ml", line 42, characters 15-28:
Error: Uninterpreted extension 'sedlex.regexp'.

Howdy! I'm having some trouble building. Perhaps it is just a question of not having the right packages installed via OPAM.

First of all, the build begins with this:

oasis setup-clean
oasis setup
W: Cannot find source file matching module 'My_Tokens' in library parser.
W: Use InterfacePatterns or ImplementationPatterns to define this file with feature "source_patterns".

Second, at the end, I get this, which seems to be the bad part:

• /Users/perry/.opam/4.05.0/bin/ocamlfind ocamldep -package sedlex -package ppx_import -package core -package compiler-libs.common -package MenhirLib -package ppx_deriving,ppx_deriving.eq,ppx_deriving.enum,ppx_deriving.show,ppx_jane -modules src/My_Lexer.mli > src/My_Lexer.mli.depends
  File "src/My_Lexer.mli", line 1, characters 58-67:
  Error: Cannot locate deriver enumerate
  Command exited with code 2.
  Compilation unsuccessful after building 1 target (0 cached) in 00:00:00.
  E: Failure("Command ''/Users/perry/.opam/4.05.0/bin/ocamlbuild' src/parser.cma test.byte -use-ocamlfind -use-menhir -cflags -w,@5+8@11@12-40,-short-paths -package ppx_deriving,ppx_deriving.eq,ppx_deriving.enum,ppx_deriving.show,ppx_jane -tag debug -tag tests' terminated with error code 10")
  make[1]: *** [all] Error 1
  make: *** [default] Error 2

Is it possible co compile to js_of_ocaml with this setup?
I know Core is incompatible with jsoo, but I tried just replacing it with Core_kernel and it seems to compile without problems (to native). Though I can't figure out how to compile to jsoo.

Here is my fork with Core_kernel: https://github.com/loxs/ocaml-parsing

How do I get past this

Recommend changing (libraries (core ocaml_parsing)) to (libraries (base stdio ocaml_parsing)).

So this section of the jbuild seems to imply that it's temporary:

;; generate lexer -- temporary hack while ppx_sedlex and ppx_import are incompatible with jbuilder!!
(rule
 ((targets (Lexer.sedlex.ml))
  (deps    (Lexer.cppo.sedlex.ml Tokens.ml))
  (action  (run ${bin:cppo} ${<} -n -o ${@}))))
(rule
 ((targets (Lexer.mli))
  (deps    (Lexer.cppo.mli Tokens.ml))
  (action  (run ${bin:cppo} ${<} -n -o ${@}))))
(rule
 ((targets (Lexer.ml))
  (deps    (Lexer.sedlex.ml))
  (action  (run ${ocaml_where}/../sedlex/ppx_sedlex ${<} -o ${@}))))

What part of that is the "temporary hack"; and how, specifically, is dune/jbuilder incompatible with Sedlex? Thanks!