internal static ReadOnlyCollection <XzaarExpression> ReturnReadOnlyExpressions(BlockExpression provider, ref object collection)
{
XzaarExpression tObj = collection as XzaarExpression;
if (tObj != null)
{
// otherwise make sure only one readonly collection ever gets exposed
Interlocked.CompareExchange(
ref collection,
new ReadOnlyCollection <XzaarExpression>(new BlockExpressionList(provider, tObj)),
tObj
);
}
// and return what is not guaranteed to be a readonly collection
return((ReadOnlyCollection <XzaarExpression>)collection);
}
internal BlockExpressionList(BlockExpression provider, Expression arg0)
{
_block = provider;
_arg0 = arg0;
}