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Compiler Error C3219

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'param' : generic parameter cannot be constrained by multiple non-interfaces : 'class'

It is not valid to constrain a generic parameter by two or more managed classes.

The following sample generates C3219:

// C3219.cpp
// compile with: /clr
ref class A {};
ref class B {};

generic <class T>
where T : A, B
ref class E {};   // C3219

The following sample demonstrates a possible resolution:

// C3219b.cpp
// compile with: /clr /c
ref class A {};

interface struct C {};

generic <class T>
where T : A
ref class E {};