Ocaml parser “unterminated action” error

Question

I am new to OCaml and I am trying to create a Parser for a specific language using a parser generator - ocamllex, ocamlyacc. When i'm trying to compile my parser.mly file, I am getting the following error:

Error (with mark at =) :

File "parser.mly", line 94: unterminated action
| id = IDENTIFIER { identifier id }
;

The following is an extract from the parser.mly file:

%{
  open Ast

  let identifier name = {
    Identifier.name = name;
  }
%}

%token <int> INT
%token <string> IDENTIFIER

%start monitor
%type <Ast.Expression.t> monitor

%%

ident:
  | id = IDENTIFIER { identifier id }
;

Answer 1

Ocamlyacc does not support giving names to the parts of a rule like this. You'll either need to use $1 etc. or switch to Menhir, which does support this feature.