/// <summary>
/// Initializes a new instance of the PersistentDictionaryLinqKeyEnumerable class.
/// </summary>
/// <param name="dict">The dictionary to enumerate.</param>
/// <param name="expression">The expression describing the range of keys to return.</param>
/// <param name="predicate">Predicate to apply to the return values.</param>
/// <param name="isReversed">
/// A value that controls whether enumerators produced by this enumerable should be reversed.
/// </param>
public PersistentDictionaryLinqKeyEnumerable(
PersistentDictionary <TKey, TValue> dict,
Expression <Predicate <TKey> > expression,
Predicate <TKey> predicate,
bool isReversed)
{
this.dictionary = dict;
this.expression = expression;
this.predicate = predicate;
this.isReversed = isReversed;
}
/// <summary>
/// Initializes a new instance of the
/// <see cref="PersistentDictionaryReverseEnumerator{TKey,TValue,TReturn}"/> class.
/// </summary>
/// <param name="dictionary">The dictionary to enumerate.</param>
/// <param name="range">The range to enumerate.</param>
/// <param name="getter">A function that gets the value from a cursor.</param>
/// <param name="predicate">The predicate to filter items with.</param>
public PersistentDictionaryReverseEnumerator(
PersistentDictionary <TKey, TValue> dictionary,
KeyRange <TKey> range,
Func <PersistentDictionaryCursor <TKey, TValue>, TReturn> getter,
Predicate <TReturn> predicate)
{
this.dictionary = dictionary;
this.range = range;
this.getter = getter;
this.predicate = predicate;
}
/// <summary>
/// Initializes a new instance of the PersistentDictionaryCollection class.
/// </summary>
/// <param name="dictionary">
/// The dictionary being enumerated to provide the collection.
/// </param>
protected PersistentDictionaryCollection(PersistentDictionary <TKey, TValue> dictionary)
{
this.dictionary = dictionary;
}
/// <summary>
/// Initializes a new instance of the PersistentDictionaryValueCollection class.
/// </summary>
/// <param name="dictionary">The dictionary containing the values.</param>
public PersistentDictionaryValueCollection(PersistentDictionary <TKey, TValue> dictionary) :
base(dictionary)
{
}
/// <summary>
/// Returns a number that represents how many elements in the dictionary satisfy a condition.
/// </summary>
/// <typeparam name="TKey">The type of the dictionary's keys.</typeparam>
/// <typeparam name="TValue">The type of the dictionary's values.</typeparam>
/// <param name="source">The dictionary.</param>
/// <param name="expression">A function to test each element for a condition.</param>
/// <returns>The number of elements that satisfy the condition.</returns>
/// <remarks>
/// This method cannot be defined on the PersistentDictonary because it conflicts
/// with the Count property.
/// </remarks>
public static int Count <TKey, TValue>(
this PersistentDictionary <TKey, TValue> source,
Expression <Predicate <KeyValuePair <TKey, TValue> > > expression) where TKey : IComparable <TKey>
{
return(source.Where(expression).Count());
}