{{{  comments
; Jump from [,{ or ( to a matching ],} or ).
; if no match can be found, a errormessage appears.
}}}
nodup
{{{  libs
{{{F pre-char.fun
:::F pre-char.fun
}}}
{{{F error.fun
:::F error.fun
}}}
}}}
{{{  goto-matching-fence
{{{  next_char op
(deffun next_char (
  O_RIGHT
  if test-end-line (
    {{{  next textline
    do (
      O_DOWN
      if test-fold-line (
        O_OPEN_FOLD
      ) else (
        if test-end-fold (O_CLOSE_FOLD) fi
      ) fi
    )
    while and(not(test-bottom),not(test-text))
      O_START_OF_LINE
    }}}
  ) fi
))
}}}
(deffun goto-matching-fence (
  if not(test-text) (oops) fi
  store-line matching-fence-y
  store-pos  matching-fence-x
  case
    {{{   {
    (test-char "{ (
      set-counter fence-counter 1
      do (
        {{{  check one character
        next_char
        if test-char "{ (
          add-counter fence-counter 1
        ) else (
          if test-char "} (add-counter fence-counter -1) fi
        ) fi
        }}}
      ) while and(not(test-bottom),not(counter-0 fence-counter))
      {{{  not found ?
      if test-bottom (
        goto-line-counter matching-fence-y
        goto-counter matching-fence-x
        failed
      ) fi
      }}}
    ))
    }}}
    {{{   }
    (test-char "} (
      set-counter fence-counter 1
      do (
        {{{  check one character
        previous-text-character
        if test-char "} (
          add-counter fence-counter 1
        ) else (
          if test-char "{ (add-counter fence-counter -1) fi
        ) fi
        }}}
      ) while and(not(counter-0 fence-counter),not(test-top))
      {{{  not found ?
      if test-top (
        goto-line-counter matching-fence-y
        goto-counter matching-fence-x
        failed
      ) fi
      }}}
    ))
    }}}
    {{{   [
    (test-char "[ (
      set-counter fence-counter 1
      do (
        {{{  check one character
        next_char
        if test-char "[ (
          add-counter fence-counter 1
        ) else (
          if test-char "] (add-counter fence-counter -1) fi
        ) fi
        }}}
      ) while and(not(test-bottom),not(counter-0 fence-counter))
      {{{  not found ?
      if test-bottom (
        goto-line-counter matching-fence-y
        goto-counter matching-fence-x
        failed
      ) fi
      }}}
    ))
    }}}
    {{{   ]
    (test-char "] (
      set-counter fence-counter 1
      do (
        {{{  check one character
        previous-text-character
        if test-char "] (
          add-counter fence-counter 1
        ) else (
          if test-char "[ (add-counter fence-counter -1) fi
        ) fi
        }}}
      ) while and(not(counter-0 fence-counter),not(test-top))
      {{{  not found ?
      if test-top (
        goto-line-counter matching-fence-y
        goto-counter matching-fence-x
        failed
      ) fi
      }}}
    ))
    }}}
    {{{   (
    (test-char "( (
      set-counter fence-counter 1
      do (
        {{{  check one character
        next_char
        if test-char "( (
          add-counter fence-counter 1
        ) else (
          if test-char ") (add-counter fence-counter -1) fi
        ) fi
        }}}
      ) while and(not(test-bottom),not(counter-0 fence-counter))
      {{{  not found ?
      if test-bottom (
        goto-line-counter matching-fence-y
        goto-counter matching-fence-x
        failed
      ) fi
      }}}
    ))
    }}}
    {{{   )
    (test-char ") (
      set-counter fence-counter 1
      do (
        {{{  check one character
        previous-text-character
        if test-char ") (
          add-counter fence-counter 1
        ) else (
          if test-char "( (add-counter fence-counter -1) fi
        ) fi
        }}}
      ) while and(not(counter-0 fence-counter),not(test-top))
      {{{  not found ?
      if test-top (
        goto-line-counter matching-fence-y
        goto-counter matching-fence-x
        failed
      ) fi
      }}}
    ))
    }}}
  esac
))
}}}