Function cursive::view::scroll::draw_box_frame

pub fn draw_box_frame<T, IsHDelim, IsVDelim>(
    scroller: &T, 
    printer: &Printer<'_, '_>, 
    is_h_delim: IsHDelim, 
    is_v_delim: IsVDelim
) where
    T: Scroller,
    IsHDelim: Fn(&T, usize) -> bool,
    IsVDelim: Fn(&T, usize) -> bool, 

Draws a box-style frame around a scrollable content.

Assumes horizontal lines are present in the content whenever is_h_delim returns true (and vertical lines when is_v_delim returns true).

It will print a box with the appropriate ├, ┤ and so on.