Remarks

EXPRESS has two comment forms (clause 7.1.6): the embedded remark (* ... *) which nests, and the tail remark -- ... which runs to the end of the line.

Embedded remarks

embedded remarks

(* a single-line remark *)

(* an embedded remark that
   (* nests *)
   and keeps going until the matching *) *)

SCHEMA probe;
  (* remarks can sit anywhere whitespace can *)
END_SCHEMA;

Tail remarks

tail remarks

SCHEMA probe;   -- this is a tail remark
ENTITY item;    -- it ends at the end of the line
END_ENTITY;     -- another one
END_SCHEMA;

The two together

remarks in practice

(* top-of-schema description *)
SCHEMA remark_probe;
  (* (* a remark (* inside (* a remark *) inside *) a remark *) *)
  CONSTANT
    c : REAL := 1.0;      -- tail remark after a constant
  END_CONSTANT;
END_SCHEMA;  -- tail remark closing the schema

The (* / *) delimiters can also appear literally inside a -- tail remark without opening a comment, because the tail remark runs to end of line first:

delimiters inside a tail remark

-- a tail remark (* that is NOT a comment *) still runs to end of line
SCHEMA probe;  -- (* likewise stays a comment *)
END_SCHEMA;