You are an expert in writing code in many different languages. Your goal is to perform code completion for the following code, keeping in mind the rest of the code and the file meta data.
    Metadata details:
    filename: multiples.rs
    path of file: ./repos/c2rust/c2rust-transpile/src/cfg
    
    the code of the file until where you have to start completion: //! This module contains stuff related to preserving and using information from the initial C
//! source to better decide when to produce `Multiple` structures instead of `Loop` structures.
//! By default, relooper always makes loops. This sometimes lea
    
    pub fn add_multiple(&mut self, join: Lbl, arms: Vec<(Lbl, IndexSet<Lbl>)>) {
        let entry_set: BTreeSet<Lbl> = arms.iter().map(|&(ref l, _)| l.clone()).collect();
        let arm_map: IndexMap<Lbl, IndexSet<Lbl>> = arms.into_iter().collect();

        if arm_map.len() > 1 {
            self.multiples.insert(entry_set, (join, arm_map));
        }
    }