Option is a type that represents either having a value (Some) or not
having a value (None).
- Implementers
- Available Extensions
- Annotations
-
Properties
-
hashCode
→ int
-
The hash code for this object.
no setterinherited
-
isNone
→ bool
-
Returns
true if the option is None.
no setter
-
isSome
→ bool
-
Returns
true if the option is Some.
no setter
-
runtimeType
→ Type
-
A representation of the runtime type of the object.
no setterinherited
Methods
-
and<U>(Option<U> optb)
→ Option<U>
-
Returns None if the option is None, otherwise returns
optb.
-
andThen<U>(Option<U> f(T value))
→ Option<U>
-
Returns None if the option is None, otherwise calls
f with the
wrapped value and returns the result.
-
expect(String msg)
→ T
-
Returns the contained Some value, consuming the
this value.
-
filter(bool predicate(T value))
→ Option<T>
-
Returns None if the option is None, otherwise calls
predicate
with the wrapped value and returns:
-
iter()
→ Iterable<T>
-
Returns an iterable over the possibly contained value.
-
map<U>(U op(T value))
→ Option<U>
-
Maps an
Option<T> to Option<U> by applying a function to a contained
value.
-
mapOr<U>(U defaultValue, U f(T value))
→ U
-
Returns the provided default (if None), or
applies a function to the contained value (if Some),
-
mapOrElse<U>(U defaultF(), U f(T value))
→ U
-
Computes a default function result (if None), or
applies a different function to the contained value (if Some).
-
noSuchMethod(Invocation invocation)
→ dynamic
-
Invoked when a nonexistent method or property is accessed.
inherited
-
okOr<E>(E err)
→ Result<T, E>
-
Transforms the Option into a Result, mapping
Some(v) to
Ok(v) and None to Err(err).
-
okOrElse<E>(E err())
→ Result<T, E>
-
Transforms the Option into a Result, mapping
Some(v) to
Ok(v) and None to Err(err()).
-
or(Option<T> optb)
→ Option<T>
-
Returns the option if it contains a value, otherwise returns
optb.
-
orElse(Option<T> f())
→ Option<T>
-
Returns the option if it contains a value, otherwise calls
f and
returns the result.
-
some()
→ T?
-
Converts from
Option<T> to T?.
-
toString()
→ String
-
A string representation of this object.
inherited
-
unwrap()
→ T
-
Returns the contained Some value, consuming the
this value.
-
unwrapOr(T defaultValue)
→ T
-
Returns the contained Some value or a provided default.
-
unwrapOrElse(T op())
→ T
-
Returns the contained Some value or computes it from a closure.
-
xor(Option<T> optb)
→ Option<T>
-
Returns Some if exactly one of
this, optb is Some, otherwise
returns None.
-
zip<U>(Option<U> other)
→ Option<Tuple2<T, U>>
-
Zips
this with another Option.
