Modified with trait

[loggerheads-with-binary]

Persistent to issue #17 I have modified the implementation of the strfmt function by using a crate-level exported Map trait instead of using a reference to a HashMap

The Map trait is automatically impleemeneted for std::collection::HashMap, serde_json::Map<String, Value> and for std::env::Vars. For any other custom structs it can be implemented at the user-level

This is the implementation of the trait

pub trait Map<K , V> where K: Hash + Eq + FromStr, V: DisplayStr{
    
    ///Prioritized first 
    fn get(&self, key : &K) -> Option<&V>; 


    ///Returned an owned item instead of a reference 
    ///Prioritized second
    #[allow(unused_variables)]
    fn get_owned(&self, key : &K) -> Option<V>{
        None //This is done because HashMap and serde_json Map can both return references  
    }
}

In general, the .get() method is used. However for cases where a local object is created and to be returned for the string-formatting, an object reference cannot be returned since it will be destroyed pursuant Rust's lifetime rules. Hence, in such cases .get_owned can be used which will return an owned object and not a reference.

By default, .get() is first tried. If it returns None, it tries .get_owned(). If both return None, then new_key_error is raised

Additionally, all the tests for this have also passed pursuant to cargo test

[vitiral]

Thanks!

Not related to your change, but is there really no stdlib version of this yet? Very disappointing IMO. Regardless, I don't see how this can hurt so I'll probably merge soon.

[loggerheads-with-binary]

Thanks!

Not related to your change, but is there really no stdlib version of this yet? Very disappointing IMO. Regardless, I don't see how this can hurt so I'll probably merge soon.

Yeah, there seems to be a couple of external libraries providing this trait. However, I believe given this project has zero dependencies, I implemented one within the library

Also, going through your Github issues, people seemed to be interested in compatibility with serde_json::Map, which is now compatible with as a feature.

[vitiral]

What are you thinking for version information. Does this require a semver change? I'm leaning no since no tests were changed yet they still pass.

[vitiral]

Also, I switched to serde_json = { version = "1.0.0" , optional = true } since the Map trait exists in 1.0

https://docs.rs/serde_json/1.0.0/serde_json/struct.Map.html

[vitiral]

let me know if that sounds good and I can release the version

[loggerheads-with-binary]

I believe crates.io will require some version change for a modified push
Also I believe the documentation may need to be updated. Do you want me to take care of the modified documentation or would you like to do that?

[vitiral]

Yes, please do!

I don't do rust anymore so this library is only maintained by contributors.