single property
Subject<T>
single
Implementation
Subject<T> get single => context.nest(() => ['has single element'], (actual) {
final iterator = actual.iterator;
if (!iterator.moveNext()) {
return Extracted.rejection(which: ['has no elements']);
}
final value = iterator.current;
if (iterator.moveNext()) {
return Extracted.rejection(which: ['has more than one element']);
}
return Extracted.value(value);
});