Function downcast_panic_message 

fn downcast_panic_message(payload: &(dyn Any + Send)) -> Cow<'static, str>

Available on crate feature panic and non-target_family=wasm only.

Downcasts an opaque panic payload (as returned by catch_unwind) to its message string, which it almost always is.

See: https://doc.rust-lang.org/stable/std/panic/struct.PanicHookInfo.html#method.payload