Function chrono::format::format

pub fn format<'a, I, B>(
    w: &mut Formatter<'_>, 
    date: Option<&NaiveDate>, 
    time: Option<&NaiveTime>, 
    off: Option<&(String, FixedOffset)>, 
    items: I
) -> Result where
    I: Iterator<Item = B> + Clone,
    B: Borrow<Item<'a>>, 

Tries to format given arguments with given formatting items. Internally used by DelayedFormat.