Can't parse a Vec<String>

[Yevhenii Reizner]

fn parse_languages(s: &str) -> Result<Vec<String>, &'static str> {
    let mut langs = Vec::new();
    for lang in s.split(',') {
        langs.push(lang.trim().to_string());
    }

    Ok(langs)
}

// ...

#[options(no_short, meta = "LANG", default = "en", parse(try_from_str = "parse_languages"))]
languages: Vec<String>,

error[E0308]: try expression alternatives have incompatible types
  --> src/main.rs:81:17
   |
81 | #[derive(Debug, Options)]
   |                 ^^^^^^^
   |                 |
   |                 expected struct `std::string::String`, found struct `std::vec::Vec`
   |                 help: try wrapping with a success variant: `Ok(Options)`
   |
   = note: expected type `std::string::String`
              found type `std::vec::Vec<std::string::String>`

[Murarth]

Yes, this is a minor design bug. gumdrop_derive sees a Vec<T> field and assumes that it will be expressed as a series of option values of type T; e.g. -x value0 -x value1 -x value2.

I'll add a per-field option to disable this automatic behavior.

[Murarth]

I've just pushed the commit implementing this option. Adding no_multi to the field attribute list should solve this issue.

[Yevhenii Reizner]

Thanks!