public static S FoldT <A, B, S, V>(this Map <A, Map <B, V> > map, S state, Func <S, V, S> folder) => map.Fold(state, (s, x) => x.Fold(s, folder));
/// <summary> /// Atomically folds all items in the map (in order) using the folder function provided. /// </summary> /// <typeparam name="S">State type</typeparam> /// <param name="state">Initial state</param> /// <param name="folder">Fold function</param> /// <returns>Folded state</returns> public static S fold <S, K, V>(Map <K, V> map, S state, Func <S, V, S> folder) => map.Fold(state, folder);