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Sasa v0.17.0 Released

A few new features in this release, and a few bugfixes and enhancements in MIME parsing. As before, the online docs are available on my site, the full release including experimental assemblies on Sourceforge, and the production assemblies on Nuget. The changelog:

 * sasametal can now replace columns and FK associations with enums that are
   provided separately
 * sasametal can now output an interface file, which generates an interface
   describing the database entities
 * many MIME fixes thanks to a few bug reports on Sasa discussion list
 * added System.Data, which provides useful extensions to ADO.NET and
   IQueryable, like a simple interface for batched SQL queries
 * MIME parser now accepts an optional parsing parameter that controls various
   parsing options, like how strict e-mail address formatting accepted,
   and whether HTML views should be parsed into MailMessage.Body
 * added enum as a primitive to Sasa.Dynamics IReducer and IBuilder
 * fixed Sasa.Enums.IsSequential check

Sasa.Dynamics probably isn't used much, but in my experiments I found it increasingly important to handle enums as a primitive, so type reduction and construction (IReduce and IBuild respectively) now includes it as such.

I created sasametal to ease the pain of maintaining several legacy systems that depend upon Microsoft's Linq2Sql. It first renames some associations to make them more meaningful, since Linq2Sql does a bad job of this in some cases. This made some integrations with ORMs like EntityFramework and NHibernate a little easier, but there still remained some painful points.

One of these pains was handling enums, ie. an entity set whose members are effectively fixed. Sasametal now takes enums into account via a command-line option, /enum:[file path], that accepts a file listing table-to-enum rewrites, one per line. For instance, if an entity Foo had a StatusId column with an FooStatus enum for the status, we could call sasametal like so:

C:\somepath> sasametal ...[other option]... /code:FooDb.cs /enum:enums.txt

and the enums.txt contains merely:

dbo.FooStatuses=Namespace.Statuses.FooStatus

You should provide the full table name including schema that sqlmetal would generate, and provide the fully qualified name of the enum you want to substitute. Sasametal will then eliminate the FooStatus entity and any FK associations linked to that entity, then it will update the type of any properties for that foreign key to use the enum type. The entities generated by sasametal are thus somewhat more efficient, and I've found it easier to use Linq2Sql as-is for quick projects against legacy systems.

When combined with sasametal's other new feature, generating interfaces describing the entities, it also eases the transition to more sophisticated ORMs that already handle enums.

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