Classes: Environment Diagrams

The questions below are due on Sunday August 03, 2025; 10:00:00 PM.
 
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Problem 1 - Diagramming Interface

In order to practice drawing environment diagrams, this question tasks you with using a drag-and-drop interface to construct a diagram.

The later questions on this page will ask you to develop diagrams on your own, but this question is designed to help you familiarize yourself with the interface itself.

Please use the interface below to re-create the following diagram, representing the state of the program below just before the call to Foo.__init__ returned.

class Foo():
    def __init__(self, x):
        self.bar = x

y = Foo(2)

Note that the global frame has been provided for you.

For instructions on how to use the interface, please click on the ℹ️ icon.

×

1. Drag objects into the field to construct a diagram.

2. Use dots to create lines for variable bindings and pointers.

3. Don’t like a line? Redraw from the source dot to remove.

4. Don’t like an object? Move to trash.

5. Don't like arrow placement? Try moving objects around to redraw.

6. Add annotations if you'd like. They don't affect correctness.

×
Are you sure you want to reset the diagram back to the starter state?
ℹ️
🗑️

Problem 2 - Class Definition

Create a diagram representing the result of executing the following code, consisting of a single class definition. Remember that a class object must contain its attributes: the variables and methods defined within the class.

class Foo():
    w = 8

    def __init__(self, name):
        self.name = name
Show/Hide Hints
  • There should be the global frame and three other objects: a class with 2 attributes, an int, and a function.
  • Remember to mark the enclosing frame of the function object.

×

1. Drag objects into the field to construct a diagram.

2. Use dots to create lines for variable bindings and pointers.

3. Don’t like a line? Redraw from the source dot to remove.

4. Don’t like an object? Move to trash.

5. Don't like arrow placement? Try moving objects around to redraw.

6. Add annotations if you'd like. They don't affect correctness.

×
Are you sure you want to reset the diagram back to the starter state?
ℹ️
🗑️

Problem 3 - Code to Diagram 1

Consider the following diagram:

In the box below, enter any valid Python program that, when executed, would lead to the diagram above.

Problem 4 - Code to Diagram 2

Consider the following diagram:

In the box below, enter any valid Python program that, when executed, would lead to the diagram above.

Next Exercise: Classes: Account

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