package Breccia.parser;


/** The parser has halted abnormally.  This is a final state, rendering the text cursor unusable
  * for the present text source.  It results from any occurrence of a parse error.
  *
  *     @see ParseError
  */
public interface Halt extends ParseState {


   // ━━━  P a r s e   S t a t e  ━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━━


    /** Returns true.
      */
    public default @Override boolean isFinal() { return true; }



    /** Returns false: error states may occur both initially and subsequently.
      */
    public default @Override boolean isInitial() { return false; }



    /** Returns {@linkplain Symmetry#asymmetric asymmetric}.
      */
    public default @Override Symmetry symmetry() { return Symmetry.asymmetric; }



    /** The default implementation returns {@linkplain Typestamp#error error}.
      */
    public default @Override int typestamp() { return Typestamp.halt; }}



                                                   // Copyright © 2021-2022  Michael Allan.  Licence MIT.