[Rust 2018] cannot use pest #[grammar = "..."] without #[macro_use] extern crate pest_derive;

[lucatrv]

As in subject, I understood that with Rust 2018:

#[macro_use] extern crate pest_derive;

should not be required anymore, as reported here:
https://rust-lang-nursery.github.io/edition-guide/rust-2018/macros/macro-changes.html

However, without that statement, the following code fails to compile:

#[derive(Parser)]
#[grammar = "csv.pest"]
pub struct CSVParser;

with error:

error[E0658]: The attribute grammar is currently unknown to the compiler and may have meaning added to it in the future (see issue #29642)

[steveklabnik]

Did you

use pest_derive::Parser;

?

[lucatrv]

Sorry, I just did:

use pest::Parser;

Thanks for your hint