default void beforeAssignment(@NotNull DfaValue source,
                                @NotNull DfaValue dest,
                                @NotNull DfaMemoryState state,
                                @Nullable DfaAnchor anchor) {

  }
default void beforeAssignment(@NotNull DfaValue source,
                                @NotNull DfaValue dest,
                                @NotNull DfaMemoryState state,
                                @Nullable DfaAnchor anchor)