# File lib/sym_tbl_gsub.rb, line 12
    def assert_symtbl ( my, ref )
      my_copy = Marshal.load(Marshal.dump(my))
      assert_equal ref, my.do_symtbl_gsub(symtbl)
      assert_equal my, my_copy,
                   'substitution not inplace has changed the object'
    end

# File lib/sym_tbl_gsub.rb, line 23
    def assert_symtbl! ( my, ref )
      assert_equal ref, my.do_symtbl_gsub!(symtbl)
    end

# File lib/sym_tbl_gsub.rb, line 19
    def assert_symtbl_nil ( my )
      assert_nil my.symtbl_gsub(symtbl)
    end

# File lib/sym_tbl_gsub.rb, line 27
    def assert_symtbl_nil! ( my )
      assert_nil my.symtbl_gsub!(symtbl)
    end