Trait Filler 

pub trait Filler<W, E>
where
    W: Write,
{
    // Required method
    fn fill(&mut self, output: &mut W, key: &str) -> Result<(), E>;
}

Implementers of this trait have the ability to fill template strings.

It is extremely strongly recommended that fillers only push to the output, and do not perform any other modifications of it.

I mean, if you implement Filler<String, _>, you get a &mut String and it’s possible to do other things with it, but that’s a terrible idea. I’m almost ashamed of ideas like making {␡} pop the last character, and {←rot13} ROT-13-encode what precedes it in the string.

Required Methods

fn fill(&mut self, output: &mut W, key: &str) -> Result<(), E>

Fill the value for the given key into the output string.

Implementations on Foreign Types

impl<K, V, W> Filler<W, SimpleFillerError> for &BTreeMap<K, V>

where K: Borrow<str> + Ord, V: AsRef<str>, W: Write,

Available on crate feature alloc only.

fn fill(&mut self, output: &mut W, key: &str) -> Result<(), SimpleFillerError>

impl<K, V, W> Filler<W, SimpleFillerError> for &HashMap<K, V>

where K: Borrow<str> + Eq + Hash, V: AsRef<str>, W: Write,

Available on crate feature std only.

fn fill(&mut self, output: &mut W, key: &str) -> Result<(), SimpleFillerError>

Implementors

impl<F, W, E> Filler<W, E> for F

where F: FnMut(&mut W, &str) -> Result<(), E>, W: Write,