thread 'main' panicked at $DIR/short-ice-remove-middle-frames-2.rs:56:5: debug!!! stack backtrace: 0: std::panicking::begin_panic 1: short_ice_remove_middle_frames_2::eight 2: short_ice_remove_middle_frames_2::seven::{{closure}} [... omitted 3 frames ...] 3: short_ice_remove_middle_frames_2::fifth 4: short_ice_remove_middle_frames_2::fourth::{{closure}} [... omitted 4 frames ...] 5: short_ice_remove_middle_frames_2::first 6: short_ice_remove_middle_frames_2::main 7: core::ops::function::FnOnce::call_once note: Some details are omitted, run with `RUST_BACKTRACE=full` for a verbose backtrace.