ULabelValue class

Overview

This is an union object to improve safety and convenience of objects using Enum.

Enum provides a very powerful type for a specific group of data, but at the same time it means a loss of flexibility: values not defined in Enum are either completely ignored or an exception is thrown if parsing fails. This union object exists to solve that problem.

This union object handles the KnownValue, a known enum value defined in Lexicon, and the UnknownValue, an unknown string value not defined in Lexicon. In other words, it can handle unknown values while enjoying the type safety of Enum.

Usage

// use when syntax.
final value = object.when(
  knownValue: (data) => data, // => KnownLabelValue
  unknownValue: (data) => data, // => String
);

// or simpler way.
if (object.isKnownValue) {
  print(object.knownValue); // => KnownLabelValue or null
} else if (object.isUnknownValue) {
  print(object.unknownValue); // => String or null
}
Implementers
Available extensions
Annotations
  • @freezed

Constructors

ULabelValue.knownValue({required KnownLabelValue data})
const
factory
ULabelValue.unknownValue({required String data})
const
factory

Properties

data → Object
no setterinherited
hashCode → int
The hash code for this object.
no setterinherited
isKnownValue → bool

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns true if this is known value, otherwise false.
no setter
isNotKnownValue → bool

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns true if this is not known value, otherwise false.
no setter
isNotUnknownValue → bool

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns true if this is not unknown value, otherwise false.
no setter
isUnknownValue → bool

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns true if this is unknown value, otherwise false.
no setter
knownValue → KnownLabelValue

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns known value.
no setter
knownValueOrNull → KnownLabelValue?

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns known value if this data is known, otherwise null.
no setter
runtimeType → Type
A representation of the runtime type of the object.
no setterinherited
unknownValue → String

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns unknown value.
no setter
unknownValueOrNull → String?

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns unknown value if this data is unknown, otherwise null.
no setter

Methods

map<TResult extends Object?>({required TResult knownValue(ULabelValueKnownValue value), required TResult unknownValue(ULabelValueUnknownValue value)}) → TResult
inherited
mapOrNull<TResult extends Object?>({TResult? knownValue(ULabelValueKnownValue value)?, TResult? unknownValue(ULabelValueUnknownValue value)?}) → TResult?
inherited
maybeMap<TResult extends Object?>({TResult knownValue(ULabelValueKnownValue value)?, TResult unknownValue(ULabelValueUnknownValue value)?, required TResult orElse()}) → TResult
inherited
maybeWhen<TResult extends Object?>({TResult knownValue(KnownLabelValue data)?, TResult unknownValue(String data)?, required TResult orElse()}) → TResult
inherited
noSuchMethod(Invocation invocation) → dynamic
Invoked when a nonexistent method or property is accessed.
inherited
toJson() → String

Available on ULabelValue, provided by the $ULabelValueExtension extension

Returns string value.
toString() → String
A string representation of this object.
inherited
when<TResult extends Object?>({required TResult knownValue(KnownLabelValue data), required TResult unknownValue(String data)}) → TResult
inherited
whenOrNull<TResult extends Object?>({TResult? knownValue(KnownLabelValue data)?, TResult? unknownValue(String data)?}) → TResult?
inherited

Operators

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