public Indexer Close([NotNull] Type[] typeClosures)
{
if (typeClosures == null)
{
throw new ArgumentNullException("typeClosures");
}
// Check input arrays are valid.
if (typeClosures.Length != ExtendedType.GenericArguments.Count())
{
return(null);
}
// If we haven't got any type closures, we can return this indexer.
if (typeClosures.All(t => t == null))
{
return(this);
}
// Close type
ExtendedType et = ExtendedType.CloseType(typeClosures);
// Check closure succeeded.
if (et == null)
{
return(null);
}
// Create new search.
Debug.Assert(_indexParameters.Value != null);
int pCount = _indexParameters.Value.Length;
TypeSearch[] searchTypes = new TypeSearch[pCount + 1];
Type[] typeGenericArguments = et.GenericArguments.Select(g => g.Type).ToArray();
// Search for closed
Type[] emptyTypes = Array <Type> .Empty;
for (int i = 0; i < pCount; i++)
{
Debug.Assert(_indexParameters.Value[i] != null);
Type pType = _indexParameters.Value[i].ParameterType;
searchTypes[i] = Reflection.ExpandParameterType(pType, emptyTypes, typeGenericArguments);
}
// Add return type
searchTypes[pCount] = Reflection.ExpandParameterType(
Info.PropertyType,
emptyTypes,
typeGenericArguments);
// Search for indexer on new type.
return(et.GetIndexer(searchTypes));
}