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invoice
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Refactor

This commit is contained in:
unknown 2018-05-22 23:14:49 -07:00
parent f9f51daaf4
commit c9a54715b4
2 changed files with 2 additions and 99 deletions
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4
lib/redux/product/product_selectors.dart
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@ -1,7 +1,5 @@
import 'package:invoiceninja/data/models/models.dart';
import 'package:invoiceninja/redux/app/app_state.dart';
import 'package:invoiceninja/utils/optional.dart';
bool isLoadingSelector(AppState state) => state.isLoading;
@ -29,6 +27,7 @@ List<ProductEntity> filteredProductsSelector(
}).toList();
}
/*
Optional<ProductEntity> productSelector(List<ProductEntity> products, int id) {
try {
return Optional.of(products.firstWhere((product) => product.id == id));
@ -36,3 +35,4 @@ Optional<ProductEntity> productSelector(List<ProductEntity> products, int id) {
return Optional.absent();
}
}
*/

97
lib/utils/optional.dart
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@ -1,97 +0,0 @@
import 'dart:collection';
/// A value that might be absent.
///
/// Use Optional as an alternative to allowing fields, parameters or return
/// values to be null. It signals that a value is not required and provides
/// convenience methods for dealing with the absent case.
class Optional<T> extends IterableBase<T> {
final T _value;
/// Constructs an empty Optional.
const Optional.absent() : _value = null;
/// Constructs an Optional of the given [value].
///
/// Throws [ArgumentError] if [value] is null.
Optional.of(T value) : this._value = value {
if (this._value == null) throw ArgumentError('Must not be null.');
}
/// Constructs an Optional of the given [value].
///
/// If [value] is null, returns [absent()].
const Optional.fromNullable(T value) : this._value = value;
/// Whether the Optional contains a value.
bool get isPresent => _value != null;
/// Whether the Optional contains a value.
bool get isNotPresent => _value == null;
/// Gets the Optional value.
///
/// Throws [StateError] if [value] is null.
T get value {
if (this._value == null) {
throw StateError('value called on absent Optional.');
}
return _value;
}
/// Executes a function if the Optional value is present.
void ifPresent(void ifPresent(T value)) {
if (isPresent) {
ifPresent(_value);
}
}
/// Execution a function if the Optional value is absent.
void ifAbsent(void ifAbsent()) {
if (!isPresent) {
ifAbsent();
}
}
/// Gets the Optional value with a default.
///
/// The default is returned if the Optional is [absent()].
///
/// Throws [ArgumentError] if [defaultValue] is null.
T or(T defaultValue) {
if (defaultValue == null) {
throw ArgumentError('defaultValue must not be null.');
}
return _value == null ? defaultValue : _value;
}
/// Gets the Optional value, or [null] if there is none.
T get orNull => _value;
/// Transforms the Optional value.
///
/// If the Optional is [absent()], returns [absent()] without applying the transformer.
///
/// The transformer must not return [null]. If it does, an [ArgumentError] is thrown.
Optional<S> transform<S>(S transformer(T value)) {
return _value == null
? Optional.absent()
: Optional.of(transformer(_value));
}
@override
Iterator<T> get iterator =>
isPresent ? <T>[_value].iterator : Iterable<T>.empty().iterator;
/// Delegates to the underlying [value] hashCode.
int get hashCode => _value.hashCode;
/// Delegates to the underlying [value] operator==.
bool operator ==(o) => o is Optional && o._value == _value;
String toString() {
return _value == null
? 'Optional { absent }'
: 'Optional { value: ${_value} }';
}
}