At first glance, Arrays, Tuples, and Sets in Swift might seem similar — they all store multiple values. But they’re each designed for different use cases.
What Is an Array?
Use an Array when you need an ordered list of items that can contain duplicates.
For example, a shopping cart list:
["Apple", "Banana", "Apple"]
- Keeps the order in which items are added
- Allows repeating values
- Ideal when order matters
What Is a Tuple?
Tuples are great when you want to group a fixed number of values, possibly of different types, that belong together.
Example: A function returns a user’s address as shown:
("John", "New York", 10001)
- Fixed size
- Can hold values of different types
- Useful when returning multiple values from a function
What Is a Set?
Set stores an unordered collection of unique values.
For example: tags in a blog post, where each tag must be unique.
var someSet = Set<DataType>()
- No duplicates allowed
- Order doesn’t matter
- Offers fast lookups (performance win!)
We can perform the following set operations on set properties — hope this brings back memories from your old math classes! 😉
- Union
- Intersection
- Subtraction
- Difference
- Subset
Quick Comparison Table
| Feature | Array | Tuple | Set |
|---|---|---|---|
| Order | ✅ Maintains order | Fixed order | ❌ No ordering |
| Duplicates | ✅ Allowed | ✅ Allowed | ❌ Unique only |
| Types | Same type | Multiple types | Same type |
| Mutability | Yes (if var) | Immutable size | Yes (if var) |
Did I miss any key points about Arrays, Tuples, or Sets in Swift?
Feel free to share your thoughts or tips in the comments below!
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