Swift Constants

Article by: Manish Methani

Last Updated: October 13, 2021 at 2:04pm IST
2 min 19 sec read

A swift constant is an entity that doesn’t change whereas a variable is an entity that may change.

For example, when we write

int a = 10
int a = 20
int a = 30

'a' is variable & '10' is constant. Variable 'a' value can be changed to '20' or '30' but you cannot change '10' or '20' or '30' . These are constant values. They are just the numbers.

Constant Declaration in Swift :

To declare constants in Swift 'let' keyword is used. Semicolons are not compulsory in Swift Language. But remember if you add two statements in a single line you have to use ';' as a delimiter to separate them. Otherwise, it shows a syntax error.

Syntax:-

let constantName = Constant Value

Example:-

let name = "Manish"
let a = 20
let b = 20.0

Let's create a sample playground, Goto File > New > Playground > Next.

Example:

import UIKit
let a = 20
print(a)

Run the program in the playground.

Output:

20

Type Annotations in Swift

Annotations are used to specify the type to constant. With the help of Type Annotations, it will be clear what kind of value that specific constant can store. And this can be done by placing a colon after the constant or variable name, followed by a space, followed by the name of the type to use.

Syntax:

let constantName:type = value

Example:-

import UIKit
let name: String
name = "Manish"
print(name)

let varA:Float = 30.0
print(varA)

Output :-

Manish
30.0

Print in Swift 3.1

//: Playground - noun: a place where people can play

import UIKit

let name = "Manish"
var age = 23

print("(name) age is = (age)")

Output 

Manish age is = 23

Explore Codzify Courses

PREMIUM

Learn to create the Dating App using No-Code Tool FlutterFlow

Level: Advanced

Course Fees: INR 1299/-

Apply Coupon Code: UNLOCK

4 days 100% Money Back Guarantee

Explore Curriculum
PREMIUM

Flutter Mobile App Development Course

Level: Intermediate

Course Fees: INR 1299/-

4 days 100% Money Back Guarantee

Explore Curriculum
PREMIUM

The Complete Angular Course

Level: Beginners

Course Fees: INR 1299/-

4 days 100% Money Back Guarantee

Explore Curriculum
PREMIUM

Dart Programming for Absolute Beginners

Level: Beginners

Course Fees: INR 1299/-

4 days 100% Money Back Guarantee

Coming Soon
FREE

Next.js course

Level: Beginners

Course Fees: FREE

Start Watching
FREE

Fundamentals of Computer Programming Languages

Level: Beginners

Course Fees: FREE

Start Watching
FREE

Learn HTML, CSS & Bootstrap

Level: Beginners

Course Fees: FREE

Start Watching

Latest Web Stories

1

Learn how to open WhatsApp using FlutterFlow | Step by Step Guide

Test your skills with these expert-led curated
Mock Tests.

C Programming Test

Test your C Programming skills with this comprehensive mock test on C Programming.

Take Test

Flutter Test

Solve most asked Interview Questions on Flutter and Test your foundational skills in flutter.

Take Test

GATE(CSE) Operating Systems

Solve most asked GATE Questions in Operating Systems and test your Gate Score.

Take Test

HTML,CSS Test

This is a mock test designed to help you assess your knowledge and skills in HTML and CSS.

Take Test

(GATE CSE) Data Structures & Algorithms Test

Solve most asked GATE Questions in Data Structures and Algorithms and test your Gate Score.

Take Test

Download the Codzify
Mobile App


Learn Anytime, Anywhere at your own pace. Scan the QR Code with your Mobile Camera to Download the Codzify Mobile App.

Codzify Mobile App Codzify Mobile App
Codzify Logo

Terms and Conditions    Cookie Policy   Refund Policy   Adsense Disclaimer