`((when (layout-invalid ,n-layout)
(%layout-invalid-error object ',layout))))
(eq ,n-layout ',layout)))))
((and (typep class 'basic-structure-class) layout)
`((when (layout-invalid ,n-layout)
(%layout-invalid-error object ',layout))))
(eq ,n-layout ',layout)))))
((and (typep class 'basic-structure-class) layout)