package rebelsky.pal;

/**
 * A temprary in a PAL program.  Temporaries should eventually be 
 * eliminated from programs.
 *
 * @author Samuel A. Rebelsky
 * @version 1.1 of December 2002
 */
public class Temporary
  extends Variable
{
  // +---------------+-----------------------------------------------------
  // | Static Fields |
  // +---------------+

  /** The counter of temporaries, used mostly for printing. */
  static int temps = 0;


  // +--------+------------------------------------------------------------
  // | Fields |
  // +--------+

  /** The number of the temporary. */
  int tempnum;

  /** The contents of the temporary.  Right now, we only permit integers. */
  int contents = 0;


  // +--------------+------------------------------------------------------
  // | Constructors |
  // +--------------+

  /**
   * Build a new temporary.
   */
  public Temporary() {
    this.tempnum = temps++;
  } // Label()


  // +---------+-----------------------------------------------------------
  // | Methods |
  // +---------+

  /** 
   * Get the integer stored in this temporary. 
   */
  public int iget(Computer hal)
  {
    return this.contents;
  } // iget()

  /**
   * Store an integer in the temporary.
   */
  public void iset(Computer hal, int newval)
  {
    this.contents = newval;
  } // iset(int)

  /** Convert the location to a string (usually for printing). */
  public String toString() {
    return "%tmp-" + tempnum;
  } // toString()

} // class Temporary