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iOS Swift Basics (retired) Operators Binary Operators

Lim Shan Kuo
Lim Shan Kuo
16,049 Points
Posted by Lim Shan Kuo
Lim Shan Kuo
16,049 Points

How a constants becomes mutable when a Double(area) applied? Plus its a compile language

let area = width * height
let areaInMeters = Double(area) / 10.764

constant variable area defined as int type then a Double function to change int type to double. I try understand from a compiler language angle.

1 Answer

Stone Preston
Stone Preston
42,016 Points
Stone Preston
Stone Preston
42,016 Points

the constant area does not become mutable. it does not change at all. constants values cannot change once they are set

let areaInMeters = Double(area)

passes the constant area in as an argument to the Double initializer and a new constant, areaInMeters, is created with the same value as area.

area is unchanged. it is not modified. area and areaInMeters are two completely different constants