@Contract(pure = true)
  @NotNull JavaSliceBuilder dropNesting() {
    if (myIndexNesting == 0) return this;
    return new JavaSliceBuilder(myParent, mySubstitutor, 0, mySyntheticField, myFilter.withType(DfType.TOP));
  }
@Contract(pure = true)
  @NotNull JavaSliceBuilder dropNesting()