indexing description: "Error for a non-boolean expression."; date: "$Date$"; revision: "$Revision $" deferred class VWBE inherit FEATURE_ERROR redefine build_explain end; feature -- Properties code: STRING is "VWBE"; -- Error code type: TYPE_A; where: STRING is deferred end; feature -- Output build_explain (st: STRUCTURED_TEXT) is do st.add_string (where); st.add_new_line; st.add_string ("Expression type: "); type.append_to (st); st.add_new_line; end; feature {COMPILER_EXPORTER} -- Setting set_type (t: TYPE_A) is do type := t; end; end -- class VWBE