Initialize variable using another variable's initialized value in Swift -

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so wanna is:

let margin: cgfloat = 10 let width: cgfloat = 100 - margin // used self.margin

but here's error i'm getting:

instance member 'margin' cannot used on type 'historyviewcontroller'

what should do?

let margin: cgfloat = 10 var width: cgfloat { return 100 - self.margin }

or

lazy var width: cgfloat = 100 - self.margin

this because @ instance variable initialization time, instance doesn't exist yet. using lazy initialization or computed property fix this.


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