ValidationResult<T, E> class sealed

Immutable result of a validation operation.

Use pattern matching to handle the result:

switch (result) {
  case Valid(:final value):
    print('Valid: $value');
  case Invalid(:final error):
    print('Error: $error');
  case InvalidAll(:final errors):
    print('Errors: $errors');
}

Constructors

ValidationResult.invalid(E error)
const
factory
ValidationResult.invalidAll(List<E> errors)
const
factory
ValidationResult.valid(T value)
const
factory

Properties

errorOrNull → E?
Returns the first error if invalid, or null if valid.
no setter
errors → List<E>
Returns all errors if invalid, or empty list if valid.
no setter
hashCode → int
The hash code for this object.
no setterinherited
isInvalid → bool
Returns true if this result represents an invalid value.
no setter
isValid → bool
Returns true if this result represents a valid value.
no setter
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
valueOrNull → T?
Returns the value if valid, or null if invalid.
no setter

Methods

fold<R>({required R onValid(T value), required R onInvalid(List<E> errors)}) → R
Transforms this result by applying onValid or onInvalid.
map<R>(R transform(T value)) → ValidationResult<R, E>
Maps the value if valid, returns same invalid result otherwise.
mapError<E2>(E2 transform(E error)) → ValidationResult<T, E2>
Maps the error(s) if invalid, returns same valid result otherwise. Maps the error(s) if invalid, returns same valid result otherwise.
maybeWhen<R>({R valid(T value)?, R invalid(E error)?, R invalidAll(List<E> errors)?, required R orElse()}) → R
Optional pattern matching with default fallback.
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toString() → String
A string representation of this object.
inherited
when<R>({required R valid(T value), required R invalid(E error), required R invalidAll(List<E> errors)}) → R
Exhaustive pattern matching.

Operators

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