Compiler Error C3216
Visual Studio 2015
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The latest version of this topic can be found at Compiler Error C3216.
constraint must be a generic parameter, not 'type'
A constraint was ill formed.
The following sample generates C3216:
// C3216.cpp
// compile with: /clr
interface struct A {};
generic <class T>
where F : A // C3216
// Try the following line instead:
// where T : A // C3216
ref class C {};
The following example demonstrates a possible resolution:
// C3216b.cpp
// compile with: /clr /c
interface struct A {};
generic <class T>
where T : A
ref class C {};
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