error[E0119]: conflicting implementations of trait `complex_impl_support::External` for type `(Q, complex_impl_support::M<'_, '_, '_, std::boxed::Box<_>, _, _>)`
  --> $DIR/complex-impl.rs:9:1
   |
LL | impl<R> External for (Q, R) {}
   | ^^^^^^^^^^^^^^^^^^^^^^^^^^^
   |
   = note: conflicting implementation in crate `complex_impl_support`:
           - impl<'a, 'b, 'c, T, U, V, W> External for (T, M<'a, 'b, 'c, Box<U>, V, W>)
             where <U as FnOnce<(T,)>>::Output == V, <V as Iterator>::Item == T, 'b: 'a, T: 'a, U: 'static, U: FnOnce<(T,)>, V: Iterator, V: Clone, W: Add, <W as Add>::Output: Copy;

error[E0117]: only traits defined in the current crate can be implemented for arbitrary types
  --> $DIR/complex-impl.rs:9:1
   |
LL | impl<R> External for (Q, R) {}
   | ^^^^^^^^^^^^^^^^^^^^^------
   | |                    |
   | |                    this is not defined in the current crate because tuples are always foreign
   | impl doesn't use only types from inside the current crate
   |
   = note: define and implement a trait or new type instead

error: aborting due to 2 previous errors

Some errors have detailed explanations: E0117, E0119.
For more information about an error, try `rustc --explain E0117`.