Function rational_deduction::expr::eval_composition

pub fn eval_composition<E, R, F, S, I>(terms: I) -> R where
    E: Expression + PartialEq,
    E::Group: IntoIterator<Item = E> + FromIterator<E>,
    R: Ratio<E::Group>,
    F: FnMut(E::Atom) -> E,
    S: AsMut<F>,
    I: IntoIterator<Item = (R, S)>, 

Evaluate a composition by performing each substitution and then composing ratios.