/// <summary>Pop the next item from the queue. Cannot be composed with other functions in a single transaction.</summary>
public async Task <(T Value, bool HasValue)> PopAsync(IFdbTransaction tr)
{
Contract.NotNull(tr, nameof(tr));
#if DEBUG
tr.Annotate("Pop()");
#endif
var first = await tr.GetRangeAsync(this.Subspace.ToRange(), SingleOptions);
if (first.IsEmpty)
{
#if DEBUG
tr.Annotate("Got nothing");
#endif
return(default);
public virtual Task <FdbRangeChunk> GetRangeAsync(KeySelector beginInclusive, KeySelector endExclusive, FdbRangeOptions options = null, int iteration = 0)
{
ThrowIfDisposed();
return(m_transaction.GetRangeAsync(beginInclusive, endExclusive, options, iteration));
}