Listing-20-34 uses the newly reserved "gen" keyword

[matej-almasi]

• I have searched open and closed issues and pull requests for duplicates, using these search terms:

  • listing-20-34
  • gen
  • reserved

• I have checked the latest main branch to see if this has already been fixed, in this file:

  • listings/ch20-advanced-features/listing-20-34/hello_macro/hello_macro_derive/src/lib.rs

URL to the section(s) of the book with this problem:
https://doc.rust-lang.org/nightly/book/ch20-05-macros.html#how-to-write-a-custom-derive-macro

Description of the problem:
Listing 20-34 uses "gen" as variable identifier, but "gen" is a keyword in 2024 edition.

Suggested fix:
Replace "gen" with another suitable identifier.

[chriskrycho]

Thanks for the report; this was fixed in #4241, which landed yesterday.

[matej-almasi]

Great! Thanks for closing.