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I've gotten the basics of type providers such as creating a type
let thisAssembly = Assembly.GetExecutingAssembly()
let t = ProvidedTypeDefinition(
thisAssembly,namespaceName,
xType.Attribute(xname "name").Value,
baseType = Some typeof<obj>)
but I need to be able to define record types and DU types is there any way to do this with type providers?
795
In this case the new type is the “sum” of the integer type plus the boolean type. In F#, a sum type is called a “discriminated union” type. Each component type (called a union case) must be tagged with a label (called a case identifier or tag) so that they can be told apart (“discriminated”).
A discriminated union is a union data structure that holds various objects, with one of the objects identified directly by a discriminant. The discriminant is the first item to be serialized or deserialized. A discriminated union includes both a discriminant and a component.
Discriminated unions are useful for heterogeneous data; data that can have special cases, including valid and error cases; data that varies in type from one instance to another; and as an alternative for small object hierarchies.
The concept of discriminated unions is how TypeScript differentiates between those objects and does so in a way that scales extremely well, even with larger sets of objects. As such, we had to create a new ANIMAL_TYPE property on both types that holds a single literal value we can use to check against.
Unfortunately, it's not possible to define any F# specific types like Discriminated Unions, Records, or Modules, in a type provider, only classes and namespaces, which is a bit unfortunate
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