Error due to using an ineligible type as a mixin
class X::Mixin::NotComposable is Exception { }
Thrown when a mixin with infix does or but is done with a composer that cannot be used for mixin.
For example
class B { };
1 but B;
CATCH { default { put .^name, ': ', .Str } };
# OUTPUT: «X::Mixin::NotComposable: Cannot mix in non-composable type B into object of type Int»
The compile-time equivalent of this error is X::Composition::NotComposable.
method target()
Returns the target of the failed mixin operation.
method rolish()
Returns the thing that could not act as a role for mixing it in