Trait Filler 

pub trait Filler<F> {
    // Required methods
    fn apply(&mut self, filler: F);
    fn new_empty_filler() -> F;

    // Provided method
    fn apply_with_log<L: FnMut(&str)>(&mut self, filler: F, _log: L) { ... }
}

Required Methods

fn apply(&mut self, filler: F)

Apply a filler

fn new_empty_filler() -> F

Get an empty filler instance

Provided Methods

fn apply_with_log<L: FnMut(&str)>(&mut self, filler: F, _log: L)

Apply a filler, calling log with each field name that is actually filled.

The default implementation ignores log and delegates to apply. The derive macro generates an override that calls log once per field that is actually filled (i.e. the field was empty and the filler supplied a value).

#[derive(Default, Filler)]
struct Item {
    value: Option<usize>,
}

let mut item = Item::default();
let filler = ItemFiller { value: Some(42) };

let mut filled_fields = Vec::new();
item.apply_with_log(filler, |field| filled_fields.push(field.to_string()));

assert_eq!(filled_fields, vec!["value"]);

Dyn Compatibility

This trait is not dyn compatible.

In older versions of Rust, dyn compatibility was called "object safety".

Implementors