else if (_left.isNumber() || _right.isNumber()) {
else if (_left.isNumber() && _right.isNumber()) {
  public void generateBoolean(PhpWriter out)    throws IOException  {    if (_left.isLong() && _right.isLong()) {      out.print("(");      _left.generateLong(out);      out.print(" != ");      _right.generateLong(out);      out.print(")");    }    else if (_left.isNumber() || _right.isNumber()) {      out.print("(");      _left.generateDouble(out);      out.print(" != ");      _right.generateDouble(out);      out.print(")");    }    else {      out.print("! ");      _left.generate(out);      out.print(".eq(");      _right.generate(out);      out.print(")");    }  }