public override Digit Update(int index, Leaf <TValue> leaf, Lineage lineage)
{
if (Lineage.AllowMutation(lineage))
{
return(Update_MUTATES(index, leaf));
}
#if ASSERTS
leaf.AssertNotNull();
#endif
var whereIsThisIndex = WhereIsThisIndex(index);
TChild res;
switch (whereIsThisIndex)
{
case IN_START:
case IN_MIDDLE_OF_1:
res = First.Update(index, leaf, lineage);
return(CreateCheckNull(lineage, res, Second, Third, Fourth));
case IN_START_OF_2:
case IN_MIDDLE_OF_2:
res = Second.Update(index - First.Measure, leaf, lineage);
return(CreateCheckNull(lineage, First, res, Third, Fourth));
case IN_START_OF_3:
case IN_MIDDLE_OF_3:
res = Third.Update(index - First.Measure - Second.Measure, leaf, lineage);
return(CreateCheckNull(lineage, First, Second, res, Fourth));
case IN_START_OF_4:
case IN_MIDDLE_OF_4:
res = Fourth.Update(index - First.Measure - Second.Measure - Third.Measure, leaf, lineage);
return(CreateCheckNull(lineage, First, Second, Third, res));
case IN_END:
case OUTSIDE:
throw ImplErrors.Arg_out_of_range("index", index);
default:
throw ImplErrors.Invalid_execution_path("Checked all index locations.");
}
}
public override void Insert(int index, Leaf <TValue> leaf, out Digit leftmost, out Digit rightmost, Lineage lineage)
{
#if ASSERTS
leaf.AssertNotNull();
#endif
var whereIsThisIndex = WhereIsThisIndex(index);
TChild myLeftmost;
TChild myRightmost;
leftmost = null;
rightmost = null;
switch (whereIsThisIndex)
{
case IN_START:
case IN_MIDDLE_OF_1:
First.Insert(index, leaf, out myLeftmost, out myRightmost, lineage);
if (Size == 4 && myRightmost != null)
{
leftmost = new Digit(myLeftmost, myRightmost, Second, lineage);
rightmost = MutateOrCreate(Third, Fourth, lineage);
return;
}
leftmost = myRightmost != null
? CreateCheckNull(lineage, myLeftmost, myRightmost, Second, Third)
: CreateCheckNull(lineage, myLeftmost, Second, Third, Fourth);
rightmost = null;
return;
case IN_START_OF_2:
case IN_MIDDLE_OF_2:
Second.Insert(index - First.Measure, leaf, out myLeftmost, out myRightmost, lineage);
if (Size == 4 && myRightmost != null)
{
leftmost = new Digit(First, myLeftmost, myRightmost, lineage);
rightmost = MutateOrCreate(Third, Fourth, lineage);
return;
}
leftmost = myRightmost != null
? CreateCheckNull(lineage, First, myLeftmost, myRightmost, Third)
: CreateCheckNull(lineage, First, myLeftmost, Third, Fourth);
rightmost = null;
return;
case IN_START_OF_3:
case IN_MIDDLE_OF_3:
Third.Insert(index - First.Measure - Second.Measure, leaf, out myLeftmost, out myRightmost, lineage);
if (Size == 4 && myRightmost != null)
{
leftmost = new Digit(First, Second, myLeftmost, lineage);
rightmost = MutateOrCreate(myRightmost, Fourth, lineage);
return;
}
leftmost =
myRightmost != null
? CreateCheckNull(lineage, First, Second, myLeftmost, myRightmost)
: CreateCheckNull(lineage, First, Second, myLeftmost, Fourth);
rightmost = null;
return;
case IN_START_OF_4:
case IN_MIDDLE_OF_4:
Fourth.Insert(index - Measure + Fourth.Measure, leaf, out myLeftmost, out myRightmost, lineage);
if (Size == 4 && myRightmost != null)
{
leftmost = new Digit(First, Second, Third, lineage);
rightmost = MutateOrCreate(myLeftmost, myRightmost, lineage);
return;
}
leftmost = MutateOrCreate(First, Second, Third, myLeftmost, lineage);
rightmost = null;
return;
default:
throw ImplErrors.Invalid_execution_path("");
}
}
