Remember a Story Choice

Supplied materials

• Paper and pencil; answers may also be spoken or typed.
• All cases, labels, numbers and rules are supplied on this page. No real account, private information or purchase is needed.

Learn the idea

State is information a program keeps about its current situation. A story can store a chosen item and later describe it. Our model replaces the held item whenever Take runs; Look reports the held item without changing it. This is different from storing every past item.

Apply each Take as a replacement, and let Look report the current held item. Do not assume a single current-item field keeps a list of all earlier items.

Use this supplied case: Take Key; Look. Start held=none. What does Look report after the stated events? Use the details in this example. Say which detail helped you choose. This pretend example does not tell us how every real system works.

1. Follow the worked example one step at a time. Say or draw what happens.
2. Apply each Take as a replacement, and let Look report the current held item.
3. Say which detail makes the example answer fit. Pick another answer and say why it does not fit.
4. Try the question and practice questions. Read the rule again if your answer does not match the explanation.

Check your reasoning

Your answer is temporary and is not saved to an account. Download your current answer before leaving or reloading. Written work on paper or in another app stays in your own file.

Take it further

New state: held=Lamp; Take Map replaces it; Look does not change it. Expected: Look reports Map and the current field remains Map.

Nothing here is saved to an account or sent to a teacher. The answer download includes your current choice and any checked feedback. It does not include choices from the separate More practice section. Download that section separately.