params.put("bool", true);
        params.put("dbl", 3.14);

        assertEquals("hello", groovyEngine.evaluate("return str", params));
        assertEquals(42, groovyEngine.evaluate("return num", params));
        assertEquals(true, groovyEngine.evaluate("return bool", params));
        assertEquals(3.14, groovyEngine.evaluate("return dbl", params));
    }

    /**