DEFINITION MODULE CodeGen;
(* Backend for SimpleMod2: pretty-prints the parsed program as a
   complete, ready-to-compile Modula-2 program module.

   OpenModule(name) creates "gen/<name>.mod" (directory "gen" must
   exist). Grammar actions then call Emit / Brk / Ind / Ded while
   parsing; Close finishes the file. Since the source language is a
   Modula-2 subset, re-emitted code compiles with e.g. gm2 -fiso. *)

PROCEDURE OpenModule (name: ARRAY OF CHAR);
(* Opens gen/<name>.mod for writing, resets indentation. *)

PROCEDURE Close;
(* Closes the output file (no-op if not open). *)

PROCEDURE Emit (s: ARRAY OF CHAR);
(* Writes raw text (keyword, identifier, literal, punctuation). *)

PROCEDURE Brk;
(* Newline + current indentation. *)

PROCEDURE Ind;
(* Indentation level + 1. *)

PROCEDURE Ded;
(* Indentation level - 1 (floored at 0). *)

END CodeGen.