vilppu/infrastructure.option

Option type usable with C#

Usage

Get nuget https://www.nuget.org/packages/Infrastructure.Option/

Overview

Option<T> is a simple option type usable with C#

Option.Some<T> represents an available value and Option.None<T> is non-available value.

Option is a static class that can be used to create Option<T> instances.

For more information about option types see https://en.wikipedia.org/wiki/Option_type

Examples

Creating some values

var someString = Option.Some("Example value");
var someInteger = Option.Some(12345);

Creating none values

var noneString = Option.None<string>();
var noneInteger = Option.None<int>();

Pattern matching optional values

var option = Option.Some("Example value");
var value = option is Some<string> some ? some.Value : "Someting else";

Fallback values using fluent syntax

Option<string> option = Option.None<string>();
var fallback = option.Or("Fallback value");
var anotherFallback = option.Or(() => "Fallback expression")

Option<string> option = Option.None<string>();
Option<string> anotherOption = Option.Some("Example value");
var fallback = option.Otherwise(anotherOption);
var anotherFallback = option.Otherwise(() => anotherOption);

Choosing first some value from many options

var options = new Option<string>[] {
    Option.None<string>,
    Option.Some("Example value")
};

var option = options.FirstSomeOtherwiseNone();

Mapping collection values

var collection = new Option<string>[]
    {
        Option.None<string>(),
        Option.Some("1"),
        Option.None<string>(),
        Option.None<string>(),
        Option.Some("2"),
        Option.Some("3"),
        Option.Some("4"),
        Option.None<string>(),
        Option.Some("5"),
        Option.None<string>(),
    };
var values = collection.Values(); // values is [ "1", "2", "3", "4", "5" ]