@Test
	public void obtainingStrlen() {
		Context c = new Context();
		DataFactory factory = new DataFactory();
		IVPString a = factory.createIVPString();
		StringLength string = factory.createStringLength();
		string.setString(a.getUniqueID());

		c.addString(a.getUniqueID(), "ABCDEFGHIJKLMNOPQRSTUVWXYZ");

		HashMap map = new HashMap();
		map.put(a.getUniqueID(), a);
		map.put(string.getUniqueID(), string);

		IVPNumber result = (IVPNumber) string.evaluate(c, map, factory);
		assertTrue(result.getValueType().equals(IVPValue.INTEGER_TYPE));
		assertTrue(c.getInt(result.getUniqueID()) == 26);
	}