Using Option

In programming, a routine might produce a correct result or encounter a problem. One classical example is division by zero. Dividing something by zero is mathematically undefined. If the application has a routine to divide something, and the routine encounters zero as input, the application cannot return any number. We want the application to return another type instead of a number. We need a type that can hold multiple variants of data.

In Rust, we can define an enum type, a type that can be different variants of data. An enum type might be as follows:

enum Shapes {

    None,

    Point(i8),

    Line(i8, i8),

    Rectangle {

        top: (i8, i8),

        length: u8,

        height: u8,

    },

}

Point and Line are said...