NEW! Master Swift design patterns with my latest book! >>

< Previous: Operator overloading   Next: Comparison operators >

Compound assignment operators

Swift has shorthand operators that combine one operator with an assignment, so you can change a variable in place. These look like the existing operators you know – +, -, *, and /, but they have an = on the end because they assign the result back to whatever variable you were using.

For example, if someone scored 95 in an exam but needs to be penalized 5 points, you could write this:

var score = 95
score -= 5

Similarly, you can add one string to another using +=:

var quote = "The rain in Spain falls mainly on the "
quote += "Spaniards"

Learn Swift faster!

Take your Swift learning to the next level: buy the Hacking with Swift e-book and get bonus material to help you learn faster!

< Previous: Operator overloading   Next: Comparison operators >
MASTER SWIFT NOW
Buy Practical iOS 12 Buy Pro Swift Buy Swift Design Patterns Buy Practical iOS 11 Buy Swift Coding Challenges Buy Server-Side Swift (Vapor Edition) Buy Server-Side Swift (Kitura Edition) Buy Hacking with macOS Buy Advanced iOS Volume One Buy Hacking with watchOS Buy Hacking with tvOS Buy Hacking with Swift Buy Dive Into SpriteKit Buy Swift in Sixty Seconds Buy Objective-C for Swift Developers Buy Beyond Code

Was this page useful? Let me know!

Click here to visit the Hacking with Swift store >>