Re: generics - constraint

Michael Moreno wrote:
I am trying to write a generic class where the underlying type is
either an int, a float or a double:

public class CMatrix<T>: ICloneable where VarType: int, float, double

but that does not compile.

The error message is :

'int' is not a valid constraint. A type used as a constraint must be an
interface, a non-sealed class or a type parameter.

Is it possible to do what I want?

No, I think the best you can do is write a static constructor that
checks typeof(T) and throws an exception if it isn't int, float, or
double.

Jesse

.

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