Result<T> class sealed

A sealed monadic wrapper representing the outcome of an operation that can either be a successful evaluation (_SuccessResult) or a structural breakdown (_FailureResult).

By modeling errors as values instead of throwing exceptions, it enforces compile-time exhaustive pattern matching, enhancing domain execution reliability.

Constructors

Result.failure(Failure failure): Encapsulates the given domain failure description object into an error state container.
factory
Result.success(T value): Encapsulates the provided value into a successful computation state wrapper.
factory

Properties

failureOrNull → Failure?: Yields the contained structured Failure representation if the operation failed; otherwise, returns null.
no setter
hashCode → int: Computes a precise hash configuration based on the underlying variant type hash calculation.
no setteroverride
isFailure → bool: Evaluates true if this runtime instance encapsulates a caught data failure state.
no setter
isSuccess → bool: Evaluates true if this runtime instance encapsulates an underlying successful operation outcome.
no setter
runtimeType → Type: A representation of the runtime type of the object.
no setterinherited
successOrNull → Success<T>?: Exposes the comprehensive immutable Success wrapper envelope if applicable; otherwise, yields null.
no setter
valueOrNull → T?: Unwraps and yields the domain value payload directly if the execution succeeded; otherwise, returns null.
no setter

Methods

flatMap<R>(Result<R> transform(T value)) → Result<R>: Chains sequential asynchronous or synchronous monadic operations where the transform callback yields another encapsulated Result envelope.
fold<R>({required R onSuccess(T value), required R onFailure(Failure failure)}) → R: Collapses the dual state of this result wrapper into a uniform type R.
getOrElse(T defaultValue) → T: Returns the embedded success value payload directly if present, otherwise fallbacks onto the statically provided defaultValue.
getOrElseFn(T orElse(Failure failure)) → T: Returns the embedded success value payload directly if present, otherwise invokes the functional lazy callback orElse passing down the underlying structural failure context.
getOrThrow() → T: Forces extraction of the underlying value or transforms a domain failure into a terminal runtime state exception.
map<R>(R transform(T value)) → Result<R>: Transforms the inner success value type using the provided transform mapper callback function.
mapFailure(Failure transform(Failure failure)) → Result<T>: Transforms the underlying domain failure signature using the provided error transform closure.
match<R>({required R onSuccess(Success<T> success), required R onFailure(Failure failure)}) → R: Performs state matching similarly to fold, but explicitly passes the underlying granular Success context object rather than just its unwrapped value.
noSuchMethod(Invocation invocation) → dynamic: Invoked when a nonexistent method or property is accessed.
inherited
toString() → String: Maps the string display format dynamically reflecting the current active subtype variant.
override

Operators

operator ==(Object other) → bool: Implements deep state structural equality validation across distinct Result wrappers.
override

Static Methods

combine<T>(List<Result<T>> results) → Result<List<T>>: Evaluates an array list collection of multi-source results.
fromNullable<T>(T? value, {required String errorMessage}) → Result<T>: Evaluates a nullable value reference. Converts to Result.success if the target object is present, otherwise allocates an explicit Failure mapped to the fallback errorMessage.
guard<T>(T operation()) → Result<T>: Wraps a synchronous functional code operation executing inside a localized boundary context.
guardAsync<T>(Future<T> operation()) → Future<Result<T>>: Wraps an asynchronous code execution operation tracking a standard Dart Future pipeline.
partition<T>(List<Result<T>> results) → (List<T>, List<Failure>): Partitions a non-homogeneous list collection of results into separated, isolated collections.