error: no rules expected `!` --> $DIR/macro-doc-comments-1.rs:6:5 | LL | macro_rules! outer { | ------------------ when calling this macro ... LL | //! Inner | ^^^^^^^^^ | | | no rules expected this token in macro call | inner doc comments expand to `#![doc = "..."]`, which is what this macro attempted to match | note: while trying to match `[` --> $DIR/macro-doc-comments-1.rs:2:7 | LL | (#[$outer:meta]) => () | ^ error: aborting due to 1 previous error