What you'll build
- A program to count animals.
- A program to figure out whether your friend’s concert will make or lose money.
- A program to decide how you can use your time to have a better morning.
What you'll learn
- Why writing code to solve a problem is preferable to writing things down and figuring out solutions on your own.
Key vocabulary
Introduction
People who are new to programming often think that coding is mostly about numbers. In fact, programmers actually spend much more time thinking about names. A programmer who sees an expression like 4 + 5 is usually more interested in what the 4 and 5 mean (are they minutes? marbles? grapefruits?) than that they add up to 9. Becoming skilled at naming will make you a much better programmer.
Go Build
Open the Naming and Identifiers.playground file in your course resources and follow the instructions.
Reflection Questions
What might this code be calculating?
let total = 4 + (7 * 3)
Without good names for these values, a programmer—especially one who's unfamiliar with this code—has no idea what they represent. This code could be calculating anything from the distance of a sidewalk to the area of a rug plus a remnant.
What might this code be calculating?
let totalVideoDuration = introDuration + (clipDuration * numberOfClips)
Because the code above uses clear names for its values, anybody who reads it will know it calculates the duration of a video.
Why is it important to use clear names when writing code?
Summary
You might think programming is difficult because you have to keep track of different parts of a program in your head. Seasoned programmers struggle with this, too, but they make life easier by combining calculations into groups, giving names to those groups, and then combining group names into other groups. You’ve just experienced this in this lesson's playground exercises. You gave names to some ideas, such as calculated costs for concert tickets, and then used those names to do other things, like finding out whether your musical event was a financial success.
You also took a peek at some programming terminology, like expression and declaration, which you'll be seeing again as you continue to build your knowledge. These terms might seem a bit foreign at first, but don't worry—by the end of the course, you'll be using them to describe your code without even thinking about it.
Many programmers will tell you that naming is one of the hardest problems they face. Creating clear, descriptive names reveals the intent of your code. As a result, other programmers will be able to work with your code and collaborate with you more effectively. It'll also be easier to find the errors in your code. And when you return to code you wrote months earlier, you'll be able to recall your thought process. (Remember to include your future self when you think about those "other programmers.") It's always worth the time to think carefully about names when you code your projects.
