balance-parens

This function is called when the user types a close parenthesis in the text%. If the close parenthesis that the user inserted does not match the corresponding open parenthesis and the 'framework:fixup-parens preference is #t (see preferences:get) the correct closing parenthesis is inserted. If the 'framework:paren-match preference is #t (see preferences:get) the matching open parenthesis is flashed.

• (send a-scheme:text balance-parens key-event) -> void
      key-event : (instance key-event%)