Standard Library Types in Swift: NOT PRIMATIVES

Get your terminology right

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Photo by David Izquierdo on Unsplash

If Swift doesn’t have primitive types, what does it have? What does that mean? Well…we still have…standard types….

Shall we get started?

Difficulty: Beginner | Easy | Normal | Challenging




Float: A number without a fixed number of digits before and after the decimal point

Floating Point Operations: Operations that are performed on Float types

Integer: A number that has no fractional part, that is no digits after the decimal point

Java: A general-purpose programming language, designed by Sun Microsystems. Intended to allow developers to write once, run everywhere

Primitive types: The most basic data types avaliable in the Java programming language which are boolean, byte, char, short, int, long, float and double

Value: The something that would be stored in a variable

Value types: Where a value is stored as the actual value of the item

This is Swift

In other languages (and we are going to use Java as a proxy for “other languages” here) there are basic types (Primitive types) that are embedded in the language as the basic building blocks (for example int).

Swift does not have Primitive types in this way, since anInteger defined in Swift as Int. Now this Int type is declared by Apple as being a type which is simply a struct in their documentation:

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But wait.

Integer operations are important (as are Float) in that they relate to specialised operations in the CPU (Integer operations typically take up one clock cycle, and although Floating Point Operations are generally slower they generally use a Floating Point Unit to make they faster than other operations).

So how does Swift take advantage of these rather special features of the CPU if they are functionally the same as user-defined types?

The answer? That’s below.

Swift’s Standard Libarary

Those rather nice people who have been developing the Swift language have helped us out here. Within the Standard Library for Swift they have produced what they call Fundamental data types, which include Int, Double and String.

When we use the Standard Library, the functions (in the form of libraries) we use are integrated into the latest release of Swift — saving space in your ultimate app download.

If that’s not awesome, I don’t know what is!

Even better you can explore the Standard Library through a repo — .


In this article we have explored Fundamental data types, the Standard Library and even referenced how you can explore the Standard Library. These are the type of tools that can help you become a better programmer.

I’d certainly urge you to do that…

Extend your knowledge

  • Apple have documentation for Int (HERE), and as discussed the Standard Library is HERE

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