Option<T> class sealed

Represents an optional value of type T.

An Option is either:

• Some, which contains a value of type T
• None, which does not contain a value

Adapted from Rust's Option, see more here: https://doc.rust-lang.org/std/option/index.html

Implementers

• None
• Some

Available extensions

• OptionConvenience

Annotations

• @immutable

Constructors

Option.none()

Shortcut for None.new.

const

factory

Option.some(T value)

Shortcut for Some.new.

const

factory

Properties

hashCode → int

The hash code for this object.

no setter, inherited

runtimeType → Type

A representation of the runtime type of the object.

no setter, inherited

Methods

asNullable() → T?

Available on Option<T>, provided by the OptionConvenience extension

Returns Some.value or null for None.

map<R>(R mapper(T)) → Option<R>

Available on Option<T>, provided by the OptionConvenience extension

Maps an Option

noSuchMethod(Invocation invocation) → dynamic

Invoked when a nonexistent method or property is accessed.

inherited

toString() → String

A string representation of this object.

inherited

unwrapOr(T defaultValue) → T

Available on Option<T>, provided by the OptionConvenience extension

Returns Some.value if this is a Some. Otherwise, returns defaultValue (when None).

unwrapOrElse(T defaultFn()) → T

Available on Option<T>, provided by the OptionConvenience extension

Returns Some.value if this is a Some. Otherwise, calls and returns the result of defaultFn (when None).

Operators

operator ==(Object other) → bool

The equality operator.

inherited