Function join_input_entry_and_input_map 

pub fn join_input_entry_and_input_map<T>(
    input_map: &[OutputEntry<T>],
    opt_input_map: &[Option<T>],
) -> Vec<OutputEntry<T>>
where
    T: Clone + Copy,
    usize: TryFrom<T>,
    <usize as TryFrom<T>>::Error: Debug,

Joins input/output maps from previous and next operation and returns joined input/output map.

input_map is first input map and opt_input_map is second map.