Compiler Error C3216

 

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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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