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where enum does not work !!!

I was writing a generic method with enum as the Constraint, and the compiler spat a few errors that did not directly convey me that enums cannot used as generic constraints. And I learnt the following from my investigation:-

This is an excerpt from the C# Language Specification. Enums are value types and there is no way that you can specify the System.ValueType as a constraint, as per the specification. But if you wish to specify a non-reference type as a [primary] constraint, struct can be used.

private void Method where T : struct

That does not guarantee that our generic method will not accept other value types, besides enum, for which we do not support our functionality.

During the course of investigation, I was extremely surprised to know that the numeric types like int, float etc in C# are struct. It is not far from the fact that they are value types, but it was interesting to know that they are declared as


public struct Int32 : IComparable, IFormattable, IConvertible, IComparable, IEquatable

Similar thing for other numeric types. Whereas an enum [System.Enum], though a value type, is declared as an abstract class that derives from System.ValueTypes unlike the int or float. The end result is that enums are value types but i wonder the way they are declared.

Anyway, the question still remains unresolved - why enums cannot be used as constraints, andjust the specification saying that enums cannot be used as constraints is unsatisfactory.

I am not sure if there is any other way to resolve my situation. Question open to cyber space !!!

P.S.
Refer section 25.7 through for the specification on Generic Type Constraints.

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