Java Code Examples for com.google.javascript.rhino.Token#SHNE

The following examples show how to use com.google.javascript.rhino.Token#SHNE . You can vote up the ones you like or vote down the ones you don't like, and go to the original project or source file by following the links above each example. You may check out the related API usage on the sidebar.
Example 1
Source File: NodeUtil.java    From astor with GNU General Public License v2.0 6 votes vote down vote up 
static boolean isBooleanResultHelper(Node n) {
  switch (n.getType()) {
    // Primitives
    case Token.TRUE:
    case Token.FALSE:
    // Comparisons
    case Token.EQ:
    case Token.NE:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.LT:
    case Token.GT:
    case Token.LE:
    case Token.GE:
    // Queries
    case Token.IN:
    case Token.INSTANCEOF:
    // Inversion
    case Token.NOT:
    // delete operator returns a boolean.
    case Token.DELPROP:
      return true;
    default:
      return false;
  }
}
Example 2
Source File: Cardumen_0087_s.java    From coming with MIT License 6 votes vote down vote up 
static boolean isBooleanResultHelper(Node n) {
  switch (n.getType()) {
    // Primitives
    case Token.TRUE:
    case Token.FALSE:
    // Comparisons
    case Token.EQ:
    case Token.NE:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.LT:
    case Token.GT:
    case Token.LE:
    case Token.GE:
    // Queries
    case Token.IN:
    case Token.INSTANCEOF:
    // Inversion
    case Token.NOT:
    // delete operator returns a boolean.
    case Token.DELPROP:
      return true;
    default:
      return false;
  }
}
Example 3
Source File: Closure_60_NodeUtil_t.java    From coming with MIT License 6 votes vote down vote up 
static boolean isBooleanResultHelper(Node n) {
  switch (n.getType()) {
    // Primitives
    case Token.TRUE:
    case Token.FALSE:
    // Comparisons
    case Token.EQ:
    case Token.NE:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.LT:
    case Token.GT:
    case Token.LE:
    case Token.GE:
    // Queryies
    case Token.IN:
    case Token.INSTANCEOF:
    // Inversion
    case Token.NOT:
    // delete operator returns a boolean.
    case Token.DELPROP:
      return true;
    default:
      return false;
  }
}
Example 4
Source File: Cardumen_00149_t.java    From coming with MIT License 6 votes vote down vote up 
static boolean isBooleanResultHelper(Node n) {
  switch (n.getType()) {
    // Primitives
    case Token.TRUE:
    case Token.FALSE:
    // Comparisons
    case Token.EQ:
    case Token.NE:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.LT:
    case Token.GT:
    case Token.LE:
    case Token.GE:
    // Queries
    case Token.IN:
    case Token.INSTANCEOF:
    // Inversion
    case Token.NOT:
    // delete operator returns a boolean.
    case Token.DELPROP:
      return true;
    default:
      return false;
  }
}
Example 5
Source File: PeepholeFoldConstants.java    From astor with GNU General Public License v2.0 6 votes vote down vote up 
/**
 * @param value The value to compare to "null"
 * @param op The boolean op to compare with
 * @return Whether the boolean op is true or false
 */
private static boolean compareToNull(Node value, int op) {
  boolean valueUndefined = NodeUtil.isUndefined(value);
  boolean valueNull = (Token.NULL == value.getType());
  boolean equivalent = valueUndefined || valueNull;
  switch (op) {
    case Token.EQ:
      // undefined is only equal to null or an undefined value
      return equivalent;
    case Token.NE:
      return !equivalent;
    case Token.SHEQ:
      return valueNull;
    case Token.SHNE:
      return !valueNull;
    default:
      throw new IllegalStateException("unexpected.");
  }
}
Example 6
Source File: jKali_003_s.java    From coming with MIT License 6 votes vote down vote up 
static boolean isBooleanResultHelper(Node n) {
  switch (n.getType()) {
    // Primitives
    case Token.TRUE:
    case Token.FALSE:
    // Comparisons
    case Token.EQ:
    case Token.NE:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.LT:
    case Token.GT:
    case Token.LE:
    case Token.GE:
    // Queries
    case Token.IN:
    case Token.INSTANCEOF:
    // Inversion
    case Token.NOT:
    // delete operator returns a boolean.
    case Token.DELPROP:
      return true;
    default:
      return false;
  }
}
Example 7
Source File: Closure_75_NodeUtil_s.java    From coming with MIT License 5 votes vote down vote up 
/**
 * A "simple" operator is one whose children are expressions,
 * has no direct side-effects (unlike '+='), and has no
 * conditional aspects (unlike '||').
 */
static boolean isSimpleOperatorType(int type) {
  switch (type) {
    case Token.ADD:
    case Token.BITAND:
    case Token.BITNOT:
    case Token.BITOR:
    case Token.BITXOR:
    case Token.COMMA:
    case Token.DIV:
    case Token.EQ:
    case Token.GE:
    case Token.GETELEM:
    case Token.GETPROP:
    case Token.GT:
    case Token.INSTANCEOF:
    case Token.LE:
    case Token.LSH:
    case Token.LT:
    case Token.MOD:
    case Token.MUL:
    case Token.NE:
    case Token.NOT:
    case Token.RSH:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.SUB:
    case Token.TYPEOF:
    case Token.VOID:
    case Token.POS:
    case Token.NEG:
    case Token.URSH:
      return true;

    default:
      return false;
  }
}
Example 8
Source File: NodeUtil.java    From astor with GNU General Public License v2.0 5 votes vote down vote up 
/**
 * Returns true if the operator on this node is symmetric
 */
static boolean isSymmetricOperation(Node n) {
  switch (n.getType()) {
    case Token.EQ: // equal
    case Token.NE: // not equal
    case Token.SHEQ: // exactly equal
    case Token.SHNE: // exactly not equal
    case Token.MUL: // multiply, unlike add it only works on numbers
                    // or results NaN if any of the operators is not a number
      return true;
  }
  return false;
}
Example 9
Source File: Cardumen_00200_s.java    From coming with MIT License 5 votes vote down vote up 
/**
 * A "simple" operator is one whose children are expressions,
 * has no direct side-effects (unlike '+='), and has no
 * conditional aspects (unlike '||').
 */
static boolean isSimpleOperatorType(int type) {
  switch (type) {
    case Token.ADD:
    case Token.BITAND:
    case Token.BITNOT:
    case Token.BITOR:
    case Token.BITXOR:
    case Token.COMMA:
    case Token.DIV:
    case Token.EQ:
    case Token.GE:
    case Token.GETELEM:
    case Token.GETPROP:
    case Token.GT:
    case Token.INSTANCEOF:
    case Token.LE:
    case Token.LSH:
    case Token.LT:
    case Token.MOD:
    case Token.MUL:
    case Token.NE:
    case Token.NOT:
    case Token.RSH:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.SUB:
    case Token.TYPEOF:
    case Token.VOID:
    case Token.POS:
    case Token.NEG:
    case Token.URSH:
      return true;

    default:
      return false;
  }
}
Example 10
Source File: Closure_23_PeepholeFoldConstants_t.java    From coming with MIT License 5 votes vote down vote up 
/**
 * The result of the comparison as a Boolean or null if the
 * result could not be determined.
 */
private Boolean compareAsNumbers(int op, Node left, Node right) {
  Double leftValue = NodeUtil.getNumberValue(left);
  if (leftValue == null) {
    return null;
  }
  Double rightValue = NodeUtil.getNumberValue(right);
  if (rightValue == null) {
    return null;
  }

  double lv = leftValue;
  double rv = rightValue;

  Boolean result;
  switch (op) {
    case Token.SHEQ:
    case Token.EQ:
      Preconditions.checkState(
          left.isNumber() && right.isNumber());
      result = lv == rv;
      break;
    case Token.SHNE:
    case Token.NE:
      Preconditions.checkState(
          left.isNumber() && right.isNumber());
      result = lv != rv;
      break;
    case Token.LE: result = lv <= rv; break;
    case Token.LT: result = lv <  rv; break;
    case Token.GE: result = lv >= rv; break;
    case Token.GT: result = lv >  rv; break;
    default:
      return null;  // don't handle that op
  }
  return result;
}
Example 11
Source File: Closure_132_PeepholeSubstituteAlternateSyntax_t.java    From coming with MIT License 5 votes vote down vote up 
/**
 * Try to minimize NOT nodes such as !(x==y).
 *
 * Returns the replacement for n or the original if no change was made
 */
private Node tryMinimizeNot(Node n) {
  Node parent = n.getParent();

  Node notChild = n.getFirstChild();
  // negative operator of the current one : == -> != for instance.
  int complementOperator;
  switch (notChild.getType()) {
    case Token.EQ:
      complementOperator = Token.NE;
      break;
    case Token.NE:
      complementOperator = Token.EQ;
      break;
    case Token.SHEQ:
      complementOperator = Token.SHNE;
      break;
    case Token.SHNE:
      complementOperator = Token.SHEQ;
      break;
    // GT, GE, LT, LE are not handled in this because !(x<NaN) != x>=NaN.
    default:
      return n;
  }
  Node newOperator = n.removeFirstChild();
  newOperator.setType(complementOperator);
  parent.replaceChild(n, newOperator);
  reportCodeChange();
  return newOperator;
}
Example 12
Source File: Closure_20_PeepholeSubstituteAlternateSyntax_s.java    From coming with MIT License 5 votes vote down vote up 
/**
 * Try to minimize NOT nodes such as !(x==y).
 *
 * Returns the replacement for n or the original if no change was made
 */
private Node tryMinimizeNot(Node n) {
  Node parent = n.getParent();

  Node notChild = n.getFirstChild();
  // negative operator of the current one : == -> != for instance.
  int complementOperator;
  switch (notChild.getType()) {
    case Token.EQ:
      complementOperator = Token.NE;
      break;
    case Token.NE:
      complementOperator = Token.EQ;
      break;
    case Token.SHEQ:
      complementOperator = Token.SHNE;
      break;
    case Token.SHNE:
      complementOperator = Token.SHEQ;
      break;
    // GT, GE, LT, LE are not handled in this because !(x<NaN) != x>=NaN.
    default:
      return n;
  }
  Node newOperator = n.removeFirstChild();
  newOperator.setType(complementOperator);
  parent.replaceChild(n, newOperator);
  reportCodeChange();
  return newOperator;
}
Example 13
Source File: Closure_80_NodeUtil_t.java    From coming with MIT License 5 votes vote down vote up 
/**
 * A "simple" operator is one whose children are expressions,
 * has no direct side-effects (unlike '+='), and has no
 * conditional aspects (unlike '||').
 */
static boolean isSimpleOperatorType(int type) {
  switch (type) {
    case Token.ADD:
    case Token.BITAND:
    case Token.BITNOT:
    case Token.BITOR:
    case Token.BITXOR:
    case Token.COMMA:
    case Token.DIV:
    case Token.EQ:
    case Token.GE:
    case Token.GETELEM:
    case Token.GETPROP:
    case Token.GT:
    case Token.INSTANCEOF:
    case Token.LE:
    case Token.LSH:
    case Token.LT:
    case Token.MOD:
    case Token.MUL:
    case Token.NE:
    case Token.NOT:
    case Token.RSH:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.SUB:
    case Token.TYPEOF:
    case Token.VOID:
    case Token.POS:
    case Token.NEG:
    case Token.URSH:
      return true;

    default:
      return false;
  }
}
Example 14
Source File: Closure_10_NodeUtil_t.java    From coming with MIT License 4 votes vote down vote up 
/**
 * Converts an operator's token value (see {@link Token}) to a string
 * representation.
 *
 * @param operator the operator's token value to convert
 * @return the string representation or {@code null} if the token value is
 * not an operator
 */
static String opToStr(int operator) {
  switch (operator) {
    case Token.BITOR: return "|";
    case Token.OR: return "||";
    case Token.BITXOR: return "^";
    case Token.AND: return "&&";
    case Token.BITAND: return "&";
    case Token.SHEQ: return "===";
    case Token.EQ: return "==";
    case Token.NOT: return "!";
    case Token.NE: return "!=";
    case Token.SHNE: return "!==";
    case Token.LSH: return "<<";
    case Token.IN: return "in";
    case Token.LE: return "<=";
    case Token.LT: return "<";
    case Token.URSH: return ">>>";
    case Token.RSH: return ">>";
    case Token.GE: return ">=";
    case Token.GT: return ">";
    case Token.MUL: return "*";
    case Token.DIV: return "/";
    case Token.MOD: return "%";
    case Token.BITNOT: return "~";
    case Token.ADD: return "+";
    case Token.SUB: return "-";
    case Token.POS: return "+";
    case Token.NEG: return "-";
    case Token.ASSIGN: return "=";
    case Token.ASSIGN_BITOR: return "|=";
    case Token.ASSIGN_BITXOR: return "^=";
    case Token.ASSIGN_BITAND: return "&=";
    case Token.ASSIGN_LSH: return "<<=";
    case Token.ASSIGN_RSH: return ">>=";
    case Token.ASSIGN_URSH: return ">>>=";
    case Token.ASSIGN_ADD: return "+=";
    case Token.ASSIGN_SUB: return "-=";
    case Token.ASSIGN_MUL: return "*=";
    case Token.ASSIGN_DIV: return "/=";
    case Token.ASSIGN_MOD: return "%=";
    case Token.VOID: return "void";
    case Token.TYPEOF: return "typeof";
    case Token.INSTANCEOF: return "instanceof";
    default: return null;
  }
}
Example 15
Source File: NodeUtil.java    From astor with GNU General Public License v2.0 4 votes vote down vote up 
/**
 * Determines whether the given value may be assigned to a define.
 *
 * @param val The value being assigned.
 * @param defines The list of names of existing defines.
 */
static boolean isValidDefineValue(Node val, Set<String> defines) {
  switch (val.getType()) {
    case Token.STRING:
    case Token.NUMBER:
    case Token.TRUE:
    case Token.FALSE:
      return true;

    // Binary operators are only valid if both children are valid.
    case Token.ADD:
    case Token.BITAND:
    case Token.BITNOT:
    case Token.BITOR:
    case Token.BITXOR:
    case Token.DIV:
    case Token.EQ:
    case Token.GE:
    case Token.GT:
    case Token.LE:
    case Token.LSH:
    case Token.LT:
    case Token.MOD:
    case Token.MUL:
    case Token.NE:
    case Token.RSH:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.SUB:
    case Token.URSH:
      return isValidDefineValue(val.getFirstChild(), defines)
          && isValidDefineValue(val.getLastChild(), defines);

    // Unary operators are valid if the child is valid.
    case Token.NOT:
    case Token.NEG:
    case Token.POS:
      return isValidDefineValue(val.getFirstChild(), defines);

    // Names are valid if and only if they are defines themselves.
    case Token.NAME:
    case Token.GETPROP:
      if (val.isQualifiedName()) {
        return defines.contains(val.getQualifiedName());
      }
  }
  return false;
}
Example 16
Source File: Cardumen_0014_t.java    From coming with MIT License 4 votes vote down vote up 
static int precedence(int type) {
  switch (type) {
    case Token.COMMA:  return 0;
    case Token.ASSIGN_BITOR:
    case Token.ASSIGN_BITXOR:
    case Token.ASSIGN_BITAND:
    case Token.ASSIGN_LSH:
    case Token.ASSIGN_RSH:
    case Token.ASSIGN_URSH:
    case Token.ASSIGN_ADD:
    case Token.ASSIGN_SUB:
    case Token.ASSIGN_MUL:
    case Token.ASSIGN_DIV:
    case Token.ASSIGN_MOD:
    case Token.ASSIGN: return 1;
    case Token.HOOK:   return 2;  // ?: operator
    case Token.OR:     return 3;
    case Token.AND:    return 4;
    case Token.BITOR:  return 5;
    case Token.BITXOR: return 6;
    case Token.BITAND: return 7;
    case Token.EQ:
    case Token.NE:
    case Token.SHEQ:
    case Token.SHNE:   return 8;
    case Token.LT:
    case Token.GT:
    case Token.LE:
    case Token.GE:
    case Token.INSTANCEOF:
    case Token.IN:     return 9;
    case Token.LSH:
    case Token.RSH:
    case Token.URSH:   return 10;
    case Token.SUB:
    case Token.ADD:    return 11;
    case Token.MUL:
    case Token.MOD:
    case Token.DIV:    return 12;
    case Token.INC:
    case Token.DEC:
    case Token.NEW:
    case Token.DELPROP:
    case Token.TYPEOF:
    case Token.VOID:
    case Token.NOT:
    case Token.BITNOT:
    case Token.POS:
    case Token.NEG:    return 13;

    case Token.CALL:
    case Token.GETELEM:
    case Token.GETPROP:
    // Data values
    case Token.ARRAYLIT:
    case Token.EMPTY:  // TODO(johnlenz): remove this.
    case Token.FALSE:
    case Token.FUNCTION:
    case Token.NAME:
    case Token.NULL:
    case Token.NUMBER:
    case Token.OBJECTLIT:
    case Token.REGEXP:
    case Token.STRING:
    case Token.STRING_KEY:
    case Token.THIS:
    case Token.TRUE:
      return 15;

    default: throw new Error("Unknown precedence for " +
                             Token.name(type) +
                             " (type " + type + ")");
  }
}
Example 17
Source File: Cardumen_00149_t.java    From coming with MIT License 4 votes vote down vote up 
/**
 * Determines whether the given value may be assigned to a define.
 *
 * @param val The value being assigned.
 * @param defines The list of names of existing defines.
 */
static boolean isValidDefineValue(Node val, Set<String> defines) {
  switch (val.getType()) {
    case Token.STRING:
    case Token.NUMBER:
    case Token.TRUE:
    case Token.FALSE:
      return true;

    // Binary operators are only valid if both children are valid.
    case Token.ADD:
    case Token.BITAND:
    case Token.BITNOT:
    case Token.BITOR:
    case Token.BITXOR:
    case Token.DIV:
    case Token.EQ:
    case Token.GE:
    case Token.GT:
    case Token.LE:
    case Token.LSH:
    case Token.LT:
    case Token.MOD:
    case Token.MUL:
    case Token.NE:
    case Token.RSH:
    case Token.SHEQ:
    case Token.SHNE:
    case Token.SUB:
    case Token.URSH:
      return isValidDefineValue(val.getFirstChild(), defines)
          && isValidDefineValue(val.getLastChild(), defines);

    // Unary operators are valid if the child is valid.
    case Token.NOT:
    case Token.NEG:
    case Token.POS:
      return isValidDefineValue(val.getFirstChild(), defines);

    // Names are valid if and only if they are defines themselves.
    case Token.NAME:
    case Token.GETPROP:
      if (val.isQualifiedName()) {
        return defines.contains(val.getQualifiedName());
      }
  }
  return false;
}
Example 18
Source File: Closure_74_PeepholeFoldConstants_t.java    From coming with MIT License 4 votes vote down vote up 
private Node tryFoldBinaryOperator(Node subtree) {
  Node left = subtree.getFirstChild();

  if (left == null) {
    return subtree;
  }

  Node right = left.getNext();

  if (right == null) {
    return subtree;
  }

  // If we've reached here, node is truly a binary operator.
  switch(subtree.getType()) {
    case Token.GETPROP:
      return tryFoldGetProp(subtree, left, right);

    case Token.GETELEM:
      return tryFoldGetElem(subtree, left, right);

    case Token.INSTANCEOF:
      return tryFoldInstanceof(subtree, left, right);

    case Token.AND:
    case Token.OR:
      return tryFoldAndOr(subtree, left, right);

    case Token.LSH:
    case Token.RSH:
    case Token.URSH:
      return tryFoldShift(subtree, left, right);

    case Token.ASSIGN:
      return tryFoldAssign(subtree, left, right);

    case Token.ADD:
      return tryFoldAdd(subtree, left, right);

    case Token.SUB:
    case Token.DIV:
    case Token.MOD:
      return tryFoldArithmeticOp(subtree, left, right);

    case Token.MUL:
    case Token.BITAND:
    case Token.BITOR:
    case Token.BITXOR:
      Node result = tryFoldArithmeticOp(subtree, left, right);
      if (result != subtree) {
        return result;
      }
      return tryFoldLeftChildOp(subtree, left, right);

    case Token.LT:
    case Token.GT:
    case Token.LE:
    case Token.GE:
    case Token.EQ:
    case Token.NE:
    case Token.SHEQ:
    case Token.SHNE:
      return tryFoldComparison(subtree, left, right);

    default:
      return subtree;
  }
}
Example 19
Source File: Closure_60_NodeUtil_s.java    From coming with MIT License 4 votes vote down vote up 
/**
 * Converts an operator's token value (see {@link Token}) to a string
 * representation.
 *
 * @param operator the operator's token value to convert
 * @return the string representation or {@code null} if the token value is
 * not an operator
 */
static String opToStr(int operator) {
  switch (operator) {
    case Token.BITOR: return "|";
    case Token.OR: return "||";
    case Token.BITXOR: return "^";
    case Token.AND: return "&&";
    case Token.BITAND: return "&";
    case Token.SHEQ: return "===";
    case Token.EQ: return "==";
    case Token.NOT: return "!";
    case Token.NE: return "!=";
    case Token.SHNE: return "!==";
    case Token.LSH: return "<<";
    case Token.IN: return "in";
    case Token.LE: return "<=";
    case Token.LT: return "<";
    case Token.URSH: return ">>>";
    case Token.RSH: return ">>";
    case Token.GE: return ">=";
    case Token.GT: return ">";
    case Token.MUL: return "*";
    case Token.DIV: return "/";
    case Token.MOD: return "%";
    case Token.BITNOT: return "~";
    case Token.ADD: return "+";
    case Token.SUB: return "-";
    case Token.POS: return "+";
    case Token.NEG: return "-";
    case Token.ASSIGN: return "=";
    case Token.ASSIGN_BITOR: return "|=";
    case Token.ASSIGN_BITXOR: return "^=";
    case Token.ASSIGN_BITAND: return "&=";
    case Token.ASSIGN_LSH: return "<<=";
    case Token.ASSIGN_RSH: return ">>=";
    case Token.ASSIGN_URSH: return ">>>=";
    case Token.ASSIGN_ADD: return "+=";
    case Token.ASSIGN_SUB: return "-=";
    case Token.ASSIGN_MUL: return "*=";
    case Token.ASSIGN_DIV: return "/=";
    case Token.ASSIGN_MOD: return "%=";
    case Token.VOID: return "void";
    case Token.TYPEOF: return "typeof";
    case Token.INSTANCEOF: return "instanceof";
    default: return null;
  }
}
Example 20
Source File: Closure_80_NodeUtil_t.java    From coming with MIT License 4 votes vote down vote up 
/**
 * Converts an operator's token value (see {@link Token}) to a string
 * representation.
 *
 * @param operator the operator's token value to convert
 * @return the string representation or {@code null} if the token value is
 * not an operator
 */
static String opToStr(int operator) {
  switch (operator) {
    case Token.BITOR: return "|";
    case Token.OR: return "||";
    case Token.BITXOR: return "^";
    case Token.AND: return "&&";
    case Token.BITAND: return "&";
    case Token.SHEQ: return "===";
    case Token.EQ: return "==";
    case Token.NOT: return "!";
    case Token.NE: return "!=";
    case Token.SHNE: return "!==";
    case Token.LSH: return "<<";
    case Token.IN: return "in";
    case Token.LE: return "<=";
    case Token.LT: return "<";
    case Token.URSH: return ">>>";
    case Token.RSH: return ">>";
    case Token.GE: return ">=";
    case Token.GT: return ">";
    case Token.MUL: return "*";
    case Token.DIV: return "/";
    case Token.MOD: return "%";
    case Token.BITNOT: return "~";
    case Token.ADD: return "+";
    case Token.SUB: return "-";
    case Token.POS: return "+";
    case Token.NEG: return "-";
    case Token.ASSIGN: return "=";
    case Token.ASSIGN_BITOR: return "|=";
    case Token.ASSIGN_BITXOR: return "^=";
    case Token.ASSIGN_BITAND: return "&=";
    case Token.ASSIGN_LSH: return "<<=";
    case Token.ASSIGN_RSH: return ">>=";
    case Token.ASSIGN_URSH: return ">>>=";
    case Token.ASSIGN_ADD: return "+=";
    case Token.ASSIGN_SUB: return "-=";
    case Token.ASSIGN_MUL: return "*=";
    case Token.ASSIGN_DIV: return "/=";
    case Token.ASSIGN_MOD: return "%=";
    case Token.VOID: return "void";
    case Token.TYPEOF: return "typeof";
    case Token.INSTANCEOF: return "instanceof";
    default: return null;
  }
}