def move_successor_3
import bend-collections@1.0.0.0/src/containers/balanced_search_tree.bend as BalancedSearchTreeimport Base
318def move_successor_3(~K: Data, ~V: Data, ~cmp: K -> K -> Cmp, +source: Nat, pair_result: TreeMap<K, V, cmp> & Maybe<&2, V>) -> TreeMap<K, V, cmp> & Nat:
319 (m3, old) = pair_result
320 (m3, source)