[ L01 L02 L03 L04 L05 L06 L07 L08 L09 L10 L11 L12 L13 L14 L15 L16 L17 L18 L19 L20 L21 L22 L23 ]

Lecture 03—How to Design Data (HtDD recipe)

Before Lecture

Before beginning Lecture 03, you should have completed the following edX modules:

All material covered in the Beginning Student Language (1a) and How to Design Functions (1b) modules. That means all the sections, the videos and all the questions interspersed in those videos.
In the How to Design Data module, work through the following videos:
- cond expressions
- Data Definitions
- Atomic Non-Distinct
- HtDF With Non-Primitive Data

During Lecture

The How to Design Data (HtDD) recipe addresses a crucial issue in the design of programs—how to design the data the program operates on. Like the HtDF recipe, HtDD initially seems cumbersome and too big a tool for the job. But just as with HtDF, learning how to design data systematically now will help you greatly with the more difficult problems ahead.

Key to the HtDD recipe is starting in the domain of the problem, also known as starting with the information. Once you have identified examples of the information you begin to design a way to represent that information as data.

By the end of the lecture—including the post-lecture work—you should be able to:

Use the HtDD recipe to systematically design data definitions using atomic data (including enumerations and itemizations).
Complete all parts of the HtDD recipe for such data definitions.
Use the @htdd and @dd-template-rules metadata tags in the data design.
Design functions that consume the data from a data definition

The starter files for today are:

After Lecture

For after lecture work please complete the starter files and review the material carefully.

The solution files for today are:

Be sure to complete the before lecture section of Lecture 4 before that lecture.