How to detect if a LINQ enumeration is materialized?

Posted by Peter Lillevold on Stack Overflow See other posts from Stack Overflow or by Peter Lillevold
Published on 2010-05-18T13:30:30Z Indexed on 2010/05/18 13:41 UTC
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LINQ

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linq-to-objects

Is there some way of detecting whether an enumerable built using LINQ (to Objects in this case) have been materialized or not? Other than trying to inspect the type of the underlying collection?

Specifically, since enumerable.ToArray() will build a new array even if the underlying collection already is an array I'm looking for a way of avoiding ToArray() being called twice on the same collection.

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