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PODiscriminated unions in NHibernate
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copied!<p>I'm wondering if there's any relatively easy way to extend NHibernate to support F#'s discriminated union. Not just a single IUserType or ICompositeUserType, but something generic that I can re-use regardless of the actual contents of the DU.</p> <p>For example, suppose I have a property called RequestInfo, which is a union defined as:</p> <pre><code>type RequestInfo = | Id of int | Name of string </code></pre> <p>This compiles into an abstract RequestInfo class, with concrete subclasses Id and Name. I can get all this info out just fine with F# reflection. In this case, I could store it in the database with "RequestInfo_Tag", "RequestInfo_Id", "RequestInfo_Name". </p> <p>As I'm a NHibernate newbie, what kind of problems am I going to run into trying to follow this approach? Are more complex cases going to be impossible to deal with? For example, what about nested discriminated unions? Is there a way I can "hand off" the reading of the rest of the union to another ICompositeUserType?</p> <p>More importantly, will this mess up my querying capabilities? Meaning, will I have to know the actual column names in the DB; I won't be able to do Criteria.Eq(SomeDiscUnion) and have it all sorted out?</p> <p>I'm not looking for a complete "provide code" answer, just some general advice if this is even worth going after (and some pointers on how), or if I should just rethink my model.</p> <p>Thanks!</p> <p>P.S. Not to be rude, but if your answer consists of "use C#", it's not very helpful. </p>

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