public static ITupleFormatter <T> CreateAppender([NotNull] ITuple prefix)
{
Contract.NotNull(prefix, nameof(prefix));
return(new AnonymousTupleFormatter <T>(
(value) => prefix.Append <T>(value),
(tuple) =>
{
if (tuple.Count != prefix.Count + 1)
{
throw new ArgumentException("Tuple size is invalid", "tuple");
}
if (!TupleHelpers.StartsWith(tuple, prefix))
{
throw new ArgumentException("Tuple does not start with the expected prefix", "tuple");
}
return tuple.Last <T>();
}
));
}
/// <summary>Create a formatter that just add or remove a prefix to values</summary>
public static ITupleFormatter <T> CreateAppender(ITuple prefix)
{
if (prefix == null)
{
throw new ArgumentNullException(nameof(prefix));
}
return(new AnonymousTupleFormatter <T>(
(value) => prefix.Append <T>(value),
(tuple) =>
{
if (tuple.Count != prefix.Count + 1)
{
throw new ArgumentException("Tuple size is invalid", nameof(tuple));
}
if (!STuple.StartsWith(tuple, prefix))
{
throw new ArgumentException("Tuple does not start with the expected prefix", nameof(tuple));
}
return tuple.Last <T>();
}
));
}
public PrefixedTuple Append <T>(T value)
{
return(new PrefixedTuple(m_prefix, m_items.Append <T>(value)));
}
/// <summary>Returns the key of a specific field of an HashSet: (subspace, id, field, )</summary>
/// <param name="id"></param>
/// <param name="field"></param>
/// <returns></returns>
protected virtual Slice GetFieldKey(ITuple id, string field)
{
//REVIEW: should the id be encoded as a an embedded tuple or not?
return(this.Subspace.Keys.Pack(id.Append(field)));
}