This deep dive covers Deep Dive: Maintainable Code within Defensive Design for GCSE Computer Science. Revise Defensive Design in 3.2 Programming for GCSE Computer Science with 15 exam-style questions and 8 flashcards. This is a high-frequency topic, so it is worth revising until the explanation feels precise and repeatable. It is section 3 of 6 in this topic. Use this deep dive to connect the idea to the wider topic before moving on to questions and flashcards.
Deep Dive: Maintainable Code
| Technique | Purpose | Example |
|---|---|---|
| Comments | Explain complex logic | // Calculate discount for members |
| Indentation | Show code structure | 4 spaces inside IF blocks |
| Naming Conventions | Clear variable/function names | customerAge not x |
| Subprograms | Break code into reusable parts | function calculateTax() |
| Constants | Named values that don't change | const VAT_RATE = 0.20 |
Practice questions for Defensive Design
What is the purpose of input validation in a program?
Describe three different types of validation check, giving an example of each.
Quick recall flashcards
Why use comments?
To explain code so others can understand and maintain it
What is authentication?
Verifying a user's identity before granting access to a system