Compiling futuretest v0.1.0 (/mnt/d/GIT/futuretest)
error[E0271]: type mismatch resolving `<Failed<(), String> as futures::IntoFuture>::Error == &str`
  --> src/main.rs:13:10
   |
13 |         .and_then(|_|
   |          ^^^^^^^^ expected struct `String`, found `&str`

error[E0271]: type mismatch resolving `<Failed<(), String> as futures::IntoFuture>::Error == &str`
  --> src/main.rs:20:10
   |
20 |     core.run(f).unwrap();
   |          ^^^ expected struct `String`, found `&str`
   |
   = note: required because of the requirements on the impl of `futures::Future` for `futures::AndThen<futures::Map<futures::MapErr<Failed<(), ()>, [closure@src/main.rs:11:18: 11:43]>, [closure@src/main.rs:12:14: 12:67]>, Failed<(), String>, [closure@src/main.rs:13:19: 16:14]>`

error: aborting due to 2 previous errors

For more information about this error, try `rustc --explain E0271`.
error: could not compile `futuretest`

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