SharpJuice.Essentials

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Creation

Maybe is implemented as readonly struct. Maybe is empty when its holded value is null.

//new empty
var maybe = new Maybe<User>();
var maybe = default(Maybe<User>);

//from object
var maybe = userObject.ToMaybe();
var maybe = new Maybe<User>(userObject);

//implicit cast
Maybe<object> may = new object();
Maybe<int> maybe = 1;

void Method(Maybe<int> arg) {...}
Method(10);

Bind

Bind method performs an action on the value when maybe contains one.

Maybe<Stream> stream = ...

//Func<T,TResult>
Maybe<int> readByte = stream.Bind(s => s.ReadByte());

//Func<T,Task<TResult>>
Maybe<int> readByte = await stream.Bind(s => s.ReadAsync(...)); 

//Action<T>
stream.Bind(s => s.Flush());  

OrElse

OrElse method is opposite to Bind. It performs the action when maybe is empty.

Maybe<User> user = ...

//Func<T>
User instance = user.OrElse(() => new User());

//Func<Task<T>>
User instance = await user.OrElse(() => database.Get(...));; 

//Value
User instance = user.OrElse(anonymousUserInstance);
User instance = user.OrDefault();  

Match

Match accepts both bind and orElse actions as parameters.

Maybe<Order> order = ...

//Action<T>
order.Match(o => o.Accept(payment), () => Refund(payment, "Order not found."))

//Func<T, TResult>
Order instance = order.Match(o => o.AddLineItem(newItem), () => new Order(newItem));

Other Methods

Maybe implements IEnumerable<T>, IEquatable<Maybe<T>>, IEquatable<T>

Maybe<User> maybe = ...

bool hasValue = maybe.Any();

//Single returns value or throws InvalidOperationException
User instance = maybe.Single();

//TryGet returns flag and value
bool hasValue = maybe.TryGet(var out value);

//Throw exception when maybe contains value.
maybe.BindThrow(() => new Exception());

//Throw exception when maybe is empty
User instance = maybe.OrThrow(() => new NotFoundException());

//Dictionary extensions
IReadOnlyDictionary<string, string> dictionary = ...
Maybe<string> value = dictionary.GetValue(key);

//Cast
Maybe<Administrator> admin = maybe.As<Administrator>();

//Empty string
Maybe<string> stringValue = " ".ToMaybe(emptyAsNull: true);

Serialization

System.Text.Json serialization supported.