Wrong struct type in example comment

[m3et]

• I have searched open and closed issues and pull requests for duplicates, using these search terms:
  • enum struct mismatch
  • no-listing-04-structs-similar-to-message-enum
  • git blame
• I have checked the latest main branch to see if this has already been fixed, in this file:
  • yes sir

URL to the section(s) of the book with this problem:

book/listings/ch06-enums-and-pattern-matching/no-listing-04-structs-similar-to-message-enum/src/main.rs

Line 7 in 81a976a

struct WriteMessage(String); // tuple struct

Description of the problem:
I would assume the comment should be of type String struct instead of Tuple struct. Please clarify if I’m mistaken in my assumption.

[StefanSalewski]

Thanks for reporting. I think you are wrong. Regular structs have named fields like in C. Rust's tuple structs have fields with no names, accessed by constant index like my_struct.0 (first component). As your provided line of code defines a struct with just a data component (of type String) with no associated name, it is a tuple struct.