1error[E0277]: the size for values of type `str` cannot be known at compilation time
2 --> $DIR/opaque_not_sized.rs:4:14
3  |
44 |         type TypeR;
5  |         -----^^^^^-
6  |         |    |
7  |         |    doesn't have a size known at compile-time
8  |         required by this bound in `__AssertSized`
9  |
10  = help: within `TypeR`, the trait `Sized` is not implemented for `str`
11  = note: required because it appears within the type `TypeR`
12