hide "ext" name, but keep "HOL.ext", to ensure consistency in naming when "ext" is used by LEO-II or Satallax implicitly
hide "ext" name, but keep "HOL.ext", to ensure consistency in naming when "ext" is used by LEO-II or Satallax implicitly

MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle,MerelyAPseudonym/isabelle