error[E0433]: failed to resolve: use of undeclared crate or module `rect`
  --> $DIR/issue-101749.rs:17:13
   |
LL |     let _ = rect::area();
   |             ^^^^ use of undeclared crate or module `rect`
   |
help: you may have meant to call an instance method
   |
LL |     let _ = rect.area();
   |                 ~

error: aborting due to 1 previous error

For more information about this error, try `rustc --explain E0433`.