@Test
public void should_ConvertValueToDoubleLikeJavaScript() throws TypeConversionException {

    assertEquals(4.2, convertToDouble(num), 0d);
    assertEquals(1d, convertToDouble(_true), 0d);
    assertEquals(0d, convertToDouble(_false), 0d);
    assertEquals(0d, convertToDouble(zero), 0d);
    assertEquals(0d, convertToDouble(emptyStr), 0d);
    assertEquals(Double.NaN, convertToDouble(_null), 0d);
    assertEquals(Double.NaN, convertToDouble(nan), 0d);
    assertEquals(Double.NaN, convertToDouble(nonEmptyStr), 0d);
}