Swift

To get the first index of an item in an array in Swift, use the array.firstIndex(where:) method. For instance, let’s find the first occurrence of the string “a” in an array: Output: Don’t let the $0 notation confuse you. Here is how it works: If you are still confused about the $0 notation, feel free […]

Here’s a list of 50 Swift interview questions and answers. These questions focus on Swift programming and iOS app development. You need to know the answers to these before you get a chance to show your skills in front of a job interviewer. Also, feel free to use these Swift interview questions to practice for an exam.

In Swift, there are two types of values: To declare constants/variables in Swift: For example, to create a constant value in Swift, use the let keyword: And to create a variable in Swift, use the var keyword: Swift advises you to create constants whenever possible. You can see this in action when Xcode shows you

In Swift, a typealias is an alias for an existing type. It allows you to call one data type by another name. Using type alias in a strategic way can make your code more readable and understandable. To declare a new typealias in your project, just use this syntax: Next up, I will show you

Did you know that you can replace this simple if-else statement in Swift: With this neat one-liner expression? This is possible thanks to what is called a ternary conditional operator in Swift. For your convenience, here is the structure of a ternary operator: Where: A ternary conditional operator offers a shorthand that is a useful way to replace simple if-else statements.

In Swift, destructuring means pulling a tuple apart into multiple variables with a single assignment. Here is what tuple destructuring syntax looks like: Where: For instance, let’s create a function that returns a tuple: Now, here is one way to access the values of the tuple: But you can do this with a single line

In Swift, inout parameters allow you to change an input passed into a function. For instance, let’s create a function that changes the original value of a number variable: In this guide, you learn why inout parameters are needed in Swift and how they work. Swift Function Parameters Cannot Be Changed In Swift, changing the

Xcode refactoring tool can be a nice time saver. Better yet the refactoring features are extremely simple to learn and adapt to. Xcode refactoring engine has been around for a while, but I’m sure many of us haven’t still found it or had no time to explore its useful features. This utility tool can be