Introduction To Swift Interview Questions And answer
Swift is a powerful programming language developed by Apple Inc. This programming language is easy to learn. This has been developed for macOS, iOS, watchOS and tvOS for Apple products. A swift code was designed safely to run very fast without any interruptions or any delays, that’s how we see the fast performance in Apple products.
So if you have finally found your dream job in Swift but are wondering how to crack the Swift Interview and what could be the probable 2019 Swift Interview Questions. Every interview is different and the scope of a job is different too. Keeping this in mind we have designed the most common Swift Interview Questions and answers to help you get success in your interview.
Below are the 5 important 2019 Swift Interview Questions and answers that are frequently asked in an interview.
1. What is Swift Programming Language?
Swift programming language is mainly used to develop software applications or operating systems for Apple products. Swift is used to writing code for devices like phones, servers, desktops or any devices that can run the code. Swift is a fast and interactive programming language. In Swift, variables will always be initialized before using. For out of bound errors, array indices will be checked. Overflows will be checked for integers as well. nil values will be handled explicitly for Optionals.
The memory management is automated in Swift. Error handling supports the recovery feature if any failures occur. Swift has powerful type inference and pattern matching feature with lightweight syntax. Any complex logic and requirements can be easily achieved because of the easy syntax. Complex ideas can be expressed in a concise manner. Swift is evolving with new versions with some great features.
2. What are the features of Swift Programming Language?
The main features of Swift programming language are safe fast and expressive. The writing code will always be in a safe manner. The mistakes in the code will be identified easily before it is moved to production. Being safer, it needs stricter in writing code or using the features with many explicit declaration features. Swift has been used as a replacement for languages like C, C++ or Objective C. The syntax in Swift programming language is easy to use and write the code. Swift supports inferred types to avoid error-prone in the code.
The Memory is automatically managed in Swift. Even semicolons are not required to terminate the lines of code. The Swift APIs are much easier to read, use and maintain the code. The additional features include Generic types, fast iteration over collections, Structs with extensions support, protocols and methods, functional programming features, control flow, powerful error handling, Tuples, Multiple return values.
Let us move to the next Swift Interview Questions.
3. What are the differences between functions and methods in Swift?
This is the most frequently asked Swift Interview Questions in an interview. Functions in Swift are defined as a self-contained code that performs a particular task as per the requirement. The function will be identified by its name to call whenever that task is needed. To declare a function, func will be used. A function can be called by calling its name with a list of parameters or arguments to be passed in the parenthesis of function. -> will be used to separate the function parameters parenthesis and the functions return type. Business e and the selected columns to be viewed.
Methods in Swift are usually associated with a particular type and are also called functions. In a swift method, first parameter name will be given a name by default. A regular old function can be called anywhere which is global. Methods and functions are always associated with a particular type. Enumerations and Structures can define methods is the major difference with different languages such as C, C++, Objective C etc. Instance methods also exist which belong to a particular class that belongs to instances but not global. Instance methods will also have the same syntax as methods. An instance method will always have access to all other instance methods.
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let sortedList = listItems.mergeSort() // easily discoverable
scooter.start() // a mutating method
let sortedList = mergeSort(listItems)
4.What is the difference between let and var in Swift?
The let and var types are used to define constants and variables in the Swift programming language. Let is used to make a constant. Var is used to create a variable. The value of constant need not be declared before compilation. It doesn’t need to be known at compile time as well. But the value can be assigned any time but only once. This value can be used in many places. This value can be determined once and will be used in many places, hence the name constant.
var myNumber = 31
myNumber = 31
let myNumberConstant = 31
For constant and variable the type need not be explicitly mentioned. The compiler infers the type of variable or constant after the value is provided. A type can also be declared before assigning the value to make it clear. Values will never be converted to another type explicitly. If a conversion is needed to another type, then an explicit type casting is required for the variable.
let myWidth = “The width is ”
let width = 31
let widthConverted = myWidth + String(width)
Let us move to the next Swift Interview Questions.
5.What are the collection types available in Swift?
Swift Programming Language provides three main collection types called Arrays, Sets and Dictionaries. These three collections are used to store a collection of values. Dictionaries are not ordered collections which will have key-value pairs associations. These three data types are always clear about the types of values and keys associated with them. The different or wrong type key or values cannot be inserted into these collection types. This leads to less error-prone or types checking safety at runtime. The collection types Arrays, Sets, and Dictionaries are mutable. This means that the values can be changed and modified as per the requirement or the operations need to be done.
The best practice is to use and create the immutable collections instead of mutable ones. This will keep safe of runtime data. An Array always stores the collection of data of the same type. The same value can occur at different indices in the array. This means duplicates are allowed for this collection type. Arrays can be created empty or with default values or with some required values while declaring. Sets store distinct values and will not allow duplicates. The order is not guaranteed in Sets. Dictionary will also not guarantee the order of insertion which has the same key types and value types for all the list of key-value pairs.
This has been a guide to List Of Swift Interview Questions and answers so that the candidate can crackdown these Swift Interview Questions easily. This is the most useful article on Swift Interview Questions and answers. You may also look at the following articles to learn more –