public IEnumerable <Range <TValue> > Exclude(Range <TValue> other)
{
var current = this;
if (current.IsEmpty || other.IsFull)
{
yield return(Empty);
yield break;
}
if (other.IsEmpty)
{
yield return(this);
yield break;
}
if (current.IsFull)
{
foreach (var r in other.Invert())
{
yield return(r);
}
yield break;
}
var currentStart = current.StartValue;
var currentEnd = current.EndValue;
var otherStart = other.StartValue;
var otherEnd = other.EndValue;
var overlap = currentStart <= otherEnd && otherStart <= currentEnd;
if (!overlap)
{
yield return(current); // Nothing to exclude
}
var compareStart = currentStart.CompareTo(otherStart);
if (compareStart <= 0) // currentStart <= otherStart
{
// =====---C--------- //
// --------O-- //
// --------O---- //
// --------O--------- //
if (compareStart == 0)
{
if (!otherStart.Included && currentStart.Included)
{
var singleValueRange = new Range <TValue>(currentStart, currentStart, true, true);
yield return(singleValueRange);
}
}
else
{
var newRange = new Range <TValue>(currentStart, otherStart, currentStart.Included, !otherStart.Included);
yield return(newRange);
}
}
var compareEnd = currentEnd.CompareTo(otherEnd);
if (compareEnd >= 0) // currentEnd >= otherEnd
{
// --------C----===== //
// --------O------- //
// --------O------------ //
if (compareEnd == 0)
{
if (!otherEnd.Included && currentEnd.Included)
{
var singleValueRange = new Range <TValue>(currentEnd, currentEnd, true, true);
yield return(singleValueRange);
}
}
else
{
var newRange = new Range <TValue>(otherEnd, currentEnd, !otherEnd.Included, currentEnd.Included);
yield return(newRange);
}
}
}