12.1 Mutating Structures
12.1.1 Example: Bank Accounts
12.1.2 Testing Functions that Mutate Structures
12.1.3 Aliasing
12.1.4 Structure Mutation and the Directory
12.1.4.1 Introducing the Heap
12.1.4.2 Basic Data and the Heap
12.2 Understanding Equality
12.2.1 Equality of Data
12.2.2 Different Equality Operations
12.2.2.1 Equality in Python
12.2.2.2 Equality in Pyret
12.3 Arrays and Lists in Memory
12.4 Cyclic Data
12.4.1 Creating Cyclic Data
12.4.2 Testing Cyclic Data
12.4.3 Cycles in Practice