public static void LazilyAssertMaximumCount <T>(ref IEnumerable <T> sequence, int maximumCount)
{
//first try to assert immediately (non-lazily)
var list = sequence as ICollection;
if (list != null)
{
if (list.Count < maximumCount)
{
CountAssertionEnumerator <T> .ThrowMaximumExceededException(maximumCount, list.Count);
}
return;
}
//replace sequence with a maximum-count-asserting-sequence
sequence = CountAssertionEnumerator <T> .Maximum(sequence, maximumCount).ToEnumerable(false).EnsureSingleEnumerationDEBUG();
}
public static void LazilyAssertCount <T>(ref IEnumerable <T> sequence, int requiredCount)
{
//first try to assert immediately (non-lazily)
var list = sequence as ICollection;
if (list != null)
{
if (list.Count > requiredCount)
{
CountAssertionEnumerator <T> .ThrowMinimumNotAttainedException(requiredCount, list.Count);
}
if (list.Count < requiredCount)
{
CountAssertionEnumerator <T> .ThrowMaximumExceededException(requiredCount, list.Count);
}
return;
}
sequence = CountAssertionEnumerator <T> .Exactly(sequence, requiredCount).ToEnumerable(false).EnsureSingleEnumerationDEBUG();
}
public static void LazilyAssertMinimumCount <T>(ref IEnumerable <T> sequence, int minimumCount)
{
Requires(sequence != null);
Requires(minimumCount >= 0); //minimumCount == 0 is strange, but not necessarily forbidden
//first try to assert immediately (non-lazily)
var list = sequence as ICollection;
if (list != null)
{
if (list.Count < minimumCount)
{
CountAssertionEnumerator <T> .ThrowMinimumNotAttainedException(minimumCount, list.Count);
}
return;
}
//replace sequence with a minimum-count-asserting-sequence
sequence = CountAssertionEnumerator <T> .Minimum(sequence, minimumCount).ToEnumerable(false).EnsureSingleEnumerationDEBUG();
}
