public static IEnumerable <T> GetOrEmpty <T>(this IOption <IEnumerable <T> > option) => option.GetOrElse(Array.Empty <T>());
/// <summary>
/// Create a sequence that contains the optional item or a default value.
/// </summary>
/// <typeparam name="T">
/// The item type.
/// </typeparam>
/// <param name="optionalItem">
/// The optional item.
/// </param>
/// <param name="valueIfNotDefined">
/// The <typeparamref name="T"/> to use if <paramref name="optionalItem"/> is not defined.
/// </param>
/// <returns>
/// If <see cref="IOption{T}.IsDefined"/> is <c>true</c>, a single-element sequence containing the item; otherwise, a sequence containing <paramref name="valueIfNotDefined"/>.
/// </returns>
private static IEnumerable <T> ToSequenceOrElse <T>(this IOption <T> optionalItem, T valueIfNotDefined)
{
yield return(optionalItem.GetOrElse(valueIfNotDefined));
}
public RecipeCellViewModel(RecipeDetail detail, IOption <int> personCount, params UserAction <IRecipe>[] actions)
{
Detail = detail;
Actions = actions;
PersonCount = personCount.GetOrElse(detail.Recipe.PersonCount);
}
/// <summary>
/// Returns the value if the option is nonempty, otherwise empty enumerable.
/// </summary>
public static IEnumerable <A> Flatten <A>(this IOption <IEnumerable <A> > option)
{
return(option.GetOrElse(_ => Enumerable.Empty <A>()));
}
public BracketExpression(IOption <NullableExpressionValue> nullable, IndexerArgument[] args)
{
this.Nullable = nullable.GetOrElse(new NullableExpressionValue(false));
this.Arguments = args;
}