void ForceChunk()
{
if (_chunk != null)
{
return;
}
long count;
try
{
count = RangeCount(_start, _end, _step);
}
catch (ArithmeticException)
{
// size of total range is > Long.MAX_VALUE so must step to count
// this only happens in pathological range cases like:
// (range -9223372036854775808 9223372036854775807 9223372036854775807)
count = SteppingCount(_start, _end, _step);
}
if (count > CHUNK_SIZE)
{ // not last chunk
long nextStart = _start + (_step * CHUNK_SIZE); // cannot overflow, must be < end
_chunkNext = new LongRange(nextStart, _end, _step, _boundsCheck);
_chunk = new LongChunk(_start, _step, CHUNK_SIZE);
}
else
{ // last chunk
_chunk = new LongChunk(_start, _step, (int)count); // count must
}
}
private LongRange(long start, long end, long step, IBoundsCheck boundsCheck, LongChunk chunk, ISeq chunkNext)
{
_start = start;
_end = end;
_step = step;
_boundsCheck = boundsCheck;
_chunk = chunk;
_chunkNext = chunkNext;
}
private LongRange(IPersistentMap meta, long start, long end, long step, IBoundsCheck boundsCheck, LongChunk chunk, ISeq chunkNext)
: base(meta)
{
_start = start;
_end = end;
_step = step;
_boundsCheck = boundsCheck;
_chunk = chunk;
_chunkNext = chunkNext;
}
public override ISeq next()
{
if (_next != null)
{
return(_next);
}
ForceChunk();
if (_chunk.count() > 1)
{
LongChunk smallerChunk = (LongChunk)_chunk.dropFirst();
_next = new LongRange(smallerChunk.first(), _end, _step, _boundsCheck, smallerChunk, _chunkNext);
return(_next);
}
return(chunkedNext());
}
