error[E0308]: mismatched types --> $DIR/issue-33884.rs:6:22 | LL | stream.write_fmt(format!("message received")) | ^^^^^^^^^^^^^^^^^^^^^^^^^^^ expected `Arguments<'_>`, found `String` | = note: this error originates in the macro `format` (in Nightly builds, run with -Z macro-backtrace for more info) error: aborting due to previous error For more information about this error, try `rustc --explain E0308`.