PFNGLMAPNAMEDBUFFERPROCDart typedef
        PFNGLMAPNAMEDBUFFERPROCDart =
     Pointer<NativeType>  Function(int buffer, int access)
    
    
    
Implementation
typedef PFNGLMAPNAMEDBUFFERPROCDart =
    Pointer<NativeType> Function(int buffer, int access);