package rebelsky.compiler.pascal;

import rebelsky.parser.SymbolPrinter;

/**
 * A simple mechanism for turning symbols that are represented as
 * integers (for speed) back into strings.
 *
 * @author Samuel A. Rebelsky
 * @version 1.0 of October 2002
 */
public class PascalSymbolPrinter
  implements SymbolPrinter
{
  // +--------+------------------------------------------------------------
  // | Fields |
  // +--------+

  private String[] symbolNames;


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

  public PascalSymbolPrinter() {
    int NUM_SYMBOLS = PascalSymbols.numSymbols();
    symbolNames = new String[NUM_SYMBOLS];
    for (int i = 0; i < NUM_SYMBOLS; i++) {
      symbolNames[i] = "????";
    }
    symbolNames[PascalSymbols.EXPRESSION] = 		"<expression>";
    symbolNames[PascalSymbols.FACTOR] = 		"<factor>";
    symbolNames[PascalSymbols.IDENTIFIER_LIST] = 	"<identifier_list>";
    symbolNames[PascalSymbols.LABEL] = 			"<label>";
    symbolNames[PascalSymbols.MULTIPLYING_OPERATOR] = 	"<multiplying_operator>";
    symbolNames[PascalSymbols.TERM] = 			"<term>";
    symbolNames[PascalSymbols.TYPE_IDENTIFIER] = 	"<type_identifier>";
    symbolNames[PascalSymbols.VARIABLE] = 		"<variable>";
  } // PascalSymbolPrinter(void)


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

  /**
   * Convert a numeric symbol to a string.
   */
  public String toString(int symbol)
  {
    if ((symbol < 0) || (symbol > symbolNames.length))
      return "????";
    else
      return symbolNames[symbol];
  } // toString(int)

} // class PascalSymbolPrinter