101.school
CoursesAbout
Search...⌘K
Generate a course with AI...

    Learn Swift Step By Step

    Receive aemail containing the next unit.
    • Introduction to Swift
      • 1.1Swift Language Overview
      • 1.2Basic Syntax in Swift
      • 1.3Data Types and Variables
      • 1.4Operators and Control Flow in Swift
    • Classes,Properties and Methods in Swift
      • 2.1Introduction to Classes and Objects
      • 2.2Properties
      • 2.3Methods
      • 2.4Inheritance, Polymorphism & Protocols
    • Collection Types in Swift
      • 3.1Introduction to Arrays, Sets and Dictionaries
      • 3.2Basic Collection Operations
      • 3.3Looping Over Collections & Modifying Collections
      • 3.4Advanced Collection Types
    • Advanced Swift
      • 4.1Error Handling in Swift
      • 4.2Extensions and Protocols
      • 4.3Generics
      • 4.4Concurrency and Multi-Threading in Swift

    Introduction to Swift

    Basic Syntax in Swift

    mobile operating system by Apple Inc.

    Mobile operating system by Apple Inc.

    Swift is a powerful and intuitive programming language developed by Apple for iOS, macOS, watchOS, and tvOS app development. It's designed to give developers more freedom than ever. Swift is easy to use and open source, so anyone with an idea can create something incredible.

    Understanding Swift Syntax

    Swift syntax is designed to be easy to read and write. It eliminates entire classes of unsafe code. Syntax is the set of rules that dictate how programs written in a language must be structured. Swift's syntax is clear and concise, making it easier for developers to write and understand code.

    Writing Your First Swift Program: "Hello, World!"

    In Swift, you can write a simple "Hello, World!" program like this:

    print("Hello, World!")

    When this code is run, it will output the string "Hello, World!" to the console.

    Comments in Swift

    Comments are used to include non-executable text in your code, as a note or reminder to yourself. Comments are ignored by the Swift compiler when your code is compiled. In Swift, you can create a single line comment using two slashes // and a multiline comment using /* to start the comment and */ to end it.

    // This is a single line comment /* This is a multi-line comment */

    Swift Identifiers, Keywords and Literals

    Identifiers are names used to identify a variable, function, or any other user-defined item. In Swift, an identifier can start with a letter A to Z or a to z or an underscore _ followed by zero or more letters, underscores, and digits (0 to 9).

    Swift reserves certain names as keywords, which have special meaning in the context of the language. For example, if, else, while, do, try, etc. are keywords in Swift.

    A literal is a direct value embedded in your source code, like the number 5 or the string "Hello". Swift uses literals to initialize variables or constants for numbers, strings, arrays, dictionaries, and booleans.

    var myVariable = 10 // 'myVariable' is an identifier, '10' is a literal let myConstant = "Hello, World!" // 'myConstant' is an identifier, '"Hello, World!"' is a literal

    Understanding the basic syntax of Swift is the first step towards mastering this powerful language. As you continue to learn, you'll discover that Swift's syntax is not only easy to understand, but also a joy to use in your everyday coding.

    Test me
    Practical exercise
    Further reading

    Hey there, any questions I can help with?

    Sign in to chat
    Next up: Data Types and Variables