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
}
- Available extensions
- Annotations
-
- @freezed
Constructors
- ULabelValue.knownValue({required KnownLabelValue data})
-
constfactory
- ULabelValue.unknownValue({required String data})
-
constfactory
Properties
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
-
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