Function c2rust_refactor::util::dataflow::iterate

pub fn iterate<K, V, F>(data: &mut HashMap<K, V>, update: F) where
    K: Hash + Eq + Clone + Debug,
    F: FnMut(K, &mut V, &Ctxt<K, V>) -> bool, 

Run an iterative worklist algorithm to find a fixed point. data should be pre-initialized with data for each relevant key. This function will call update(k, v, ctx) for each node. Use ctx[other_k] to obtain data for other nodes.

TODO: Right now, indexing panics if other_k == k. If we change the signature of update to FnMut(K, &RefactorCtxt<K, V>) -> V then we can avoid this issue. Being unable to mutate the value in-place might be slightly less efficient for some use cases, though.