Result<T, E> class abstract

Result is a type that represents either success (Ok) or failure (Err).

Result<T, E> is the type used for returning and propagating errors. It is an object with an Ok value, representing success and containing a value, and Err, representing error and containing an error value.

Implementers

Constructors

Result()
Result.err(E err)
Create an Err result with the given error.
factory
Result.of(T catching())
Call the catching function and produce a Result.
factory
Result.ok(T s)
Create an Ok result with the given value.
factory

Properties

hashCode → int
The hash code for this object.
no setterinherited
props → List<Object?>
The list of properties that will be used to determine whether two instances are equal.
no setterinherited
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
stringify → bool?
If set to true, the toString method will be overridden to output this instance's props.
no setterinherited

Methods

and(Result<T, E> res) → Result<T, E>
Returns res if the result is Ok, otherwise returns this.
andThen(Result<T, E> op(T)) → Result<T, E>
Calls op with the Ok value if the result is Ok, otherwise returns this.
err() → Option<E>
Converts the Result into an Option containing the error, if any. Otherwise returns None if the result is a value.
expect(String msg) → T
Unwraps a result, yielding the content of an Ok.
expectErr(String msg) → E
Unwraps a result, yielding the content of an Err.
fold<U, F>(U ok(T), F err(E)) → Result<U, F>
Invoke either the ok or the err function based on the result.
isErr() → bool
Returns true if the option is a Err value.
isOk() → bool
Returns true if the option is a Ok value.
map<U>(U op(T)) → Result<U, E>
Maps a Result<T, E> to Result<U, E> by applying a function to a contained Ok value, leaving an Err value untouched.
mapErr<F>(F op(E)) → Result<T, F>
Maps a Result<T, E> to Result<T, F> by applying a function to a contained Err value, leaving an Ok value untouched.
mapOr<U>(U op(T), U opt) → U
Applies a function to the contained value (if any), or returns the provided default (if not).
mapOrElse<U>(U op(T), U errOp(E)) → U
Maps a Result<T, E> to U by applying a function to a contained Ok value, or a fallback function to a contained Err value.
match<R>(R okop(T), R errop(E)) → R
Invokes either the okop or the errop depending on the result.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
ok() → Option<T>
Converts the Result into an Option containing the value, if any. Otherwise returns None if the result is an error.
or(Result<T, E> res) → Result<T, E>
Returns res if the result is an Err, otherwise returns this.
orElse(Result<T, E> op(E)) → Result<T, E>
Calls op with the Err value if the result is Err, otherwise returns this.
toString() → String
A string representation of this object.
inherited
unwrap() → T
Unwraps a result, yielding the content of an Ok.
unwrapErr() → E
Unwraps a result, yielding the content of an Err.
unwrapOr(T opt) → T
Unwraps a result, yielding the content of an Ok. Else, it returns opt.
unwrapOrElse(T op(E)) → T
Unwraps a result, yielding the content of an Ok. If the value is an Err then it calls op with its value.
when<R>({required R ok(T), required R err(E)}) → R
Invokes either ok or err depending on the result.

Operators

operator ==(Object other) → bool
The equality operator.
inherited