Computed property and Stored property in Swift

Computed property

A computed variable behaves syntactically like a variable but does not actually require storage. computed property just recalculate the block of code whenever it’s called and returns the value.

In short, “A computed property is one that runs some code in order to calculate the value.”

Stored property

The simplest form of a variable declaration provides only a type. Stored variables must be initialized before use. As such, an initial value can be provided at the declaration site.

In short, A stored property is one that saves a value for use later.”

I have created one class

class MyClass {    init() {
print(“MyClass init”)
}
}

Computed property Example

var myClassObj: MyClass {    return MyClass()}print(myClassObj) //“MyClass init”print(myClassObj) //“MyClass init”
😱😱😱😱

Yes, MyClass instance is created two times here. so whenever you call Computed property it will recalculate every time.

Stored property Example

var myClassObj: MyClass = MyClass() //“MyClass init”print(myClassObj) print(myClassObj) 
🤩🤩🤩🤩

So here MyClass instance is created once. so whenever you call Stored property it will provide you the same instance.

So both have there different advantages/disadvantages

For more visit: https://ioslifee.blogspot.com

Thanks for reading, Happy Coding 💻

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