Error code E0551
Note: this error code is no longer emitted by the compiler
An invalid meta-item was used inside an attribute.
Erroneous code example:
#![allow(unused)] fn main() { #[deprecated(note)] // error! fn i_am_deprecated() {} }
Meta items are the key-value pairs inside of an attribute. To fix this issue,
you need to give a value to the note
key. Example:
#![allow(unused)] fn main() { #[deprecated(note = "because")] // ok! fn i_am_deprecated() {} }