ocaml

I'm porting my application from OCaml 4.02.3 to 4.03.0. Say you have the following in lexer.ml : type t = T [@@deriving sexp] let () = sexp_of_t |> ignore; print_endline "hai" I'm trying to run it as following: ocamlbuild -use-ocamlfind -pkg ppx_sexp_conv -cflags '-w @a-4-31' lexer.byte -- But I'm getting the following error: Warning 31: files lexer.cmo and /Users/vladimir/.opam/4.03.0+flambda/lib/ocaml/compiler-libs/ocamlcommon.cma(Lexer) both define a module named Lexer File "_none_", line 1: Error: Some fatal warnings were triggered (1 occurrences) I understand that compiler-libs has a

When loading the Graphics module in the toplevel, I get an error saying "Cannot find graphics.cma". I'm using OS X and I'm pretty sure I've installed OCaml correctly since I've been using it for about a month now. So it seems that the Graphics module wasn't included in the OCaml package. How can I fix this issue, or how can I install the Graphics module myself? First of all, check Graphics is really installed. This library is optional and therefore it may not be installed. There are several ways to check but the following should work for any situation: $ ls `ocamlc -where`/graphics* If there

Given the following type: type ('props,'state) reactInstance = { props: 'props; state: 'state; updater: 'event . (('props,'state) reactInstance -> 'event -> 'state) -> ('props,'state) reactInstance -> 'event -> unit;} I'm trying to achieve: let rec updater f instance event = let nextState = f instance event in let newInstance = { props; state = nextState; updater } in () let newInstance = { props; state = (reactClass.getInitialState ()); updater } I gave the updater a forall-like type definition. My main motivation is because the updater will get invoked with an event. No idea what that event

I'm trying to split the following recursive modules into separate compilation units. Specifically, I'd like B to be in its own b.ml, to be able to reuse it with other A's. module type AT = sig type b type t = Foo of b | Bar val f : t -> b list end module type BT = sig type a type t = { aaa: a list; bo: t option } val g : t -> t list end module rec A : (AT with type b = B.t) = struct type b = B.t type t = Foo of b | Bar let f = function Foo b -> [ b ] | Bar -> [] end and B : (BT with type a = A.t) = struct type a = A.t type t = { aaa: a list; bo: t option } let g b = let ss = List.flatten (List

I'm following this blog post: http://semantic-domain.blogspot.com/2012/12/total-functional-programming-in-partial.html It shows a small OCaml compiler program for System T (a simple total functional language) . The entire pipeline takes OCaml syntax (via Camlp4 metaprogramming) transforms them to OCaml AST that is translated to SystemT Lambda Calculus (see: module Term ) and then finally SystemT Combinator Calculus (see: module Goedel ). The final step is also wrapped with OCaml metaprogramming Ast.expr type. I'm attempting to translate it to Haskell without the use of Template Haskell. For