DAY 3

Complex data types, part 1

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Today we’re going to look at some more complex data types that group data together. Understanding the differences between them, and especially knowing which to use and when, can sometimes trip folks up when they are learning – as Joseph Campbell once said, “computers are like Old Testament gods: lots of rules and no mercy.”

Don’t worry, though: you’ll find that the three types we’re learning today cover the overwhelming majority of requirements you’ll need for grouping data, and if you choose the wrong one when you’re learning then nothing bad is going to happen.

In fact, a common mistake folks make while learning is they have a fear of running their code. Trust me on this: while you’re following all the code here, none of the code you write can somehow break your computer. So, make a change and run it. Make another change and run that. Just try changing your values until you feel comfortable with what’s happening – it all helps.

Today you have four tutorials to follow, and you’ll meet things like arrays, dictionaries, sets, and more. After watching each video you’re welcome to go through some optional extra reading if you want extra clarification on a topic, and there are some short tests to help make sure you’ve understood what was taught.

1. How to store ordered data in arrays
   • Optional: Why does Swift have arrays?
   • Test: Arrays
2. How to store and find data in dictionaries
   • Optional: Why does Swift have dictionaries as well as arrays?
   • Optional: Why does Swift have default values for dictionaries?
   • Test: Dictionaries
   • Test: Dictionary default values
3. How to use sets for fast data lookup
   • Optional: Why are sets different from arrays in Swift?
   • Test: Sets
4. How to create and use enums
   • Optional: Why does Swift need enums?
   • Test: Enumerations

You’ve finished day three now, and you’re starting to write useful Swift code – make sure to tell the world about your progress!

How can this day be improved?

Great job on finishing another day! If you still have questions about what you learned, please send them in using this form – I'll do my best to address the most common problems in the next course update. Thank you!

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