Function replace_vars

pub fn replace_vars<'a, F, S>(dirs: &mut Vec<Directive>, f: F)
where
    F: FnMut(&str) -> Option<S>,
    S: AsRef<str> + Into<String> + 'a,

A recursive mutable visitor of all variable values

This function allows to replace all occurrences of some variable. If f returns None variable is skipped.