editing_arg_idx(win_T *win)
{
    return !(win->w_arg_idx >= WARGCOUNT(win)
		|| (win->w_buffer->b_fnum
				      != WARGLIST(win)[win->w_arg_idx].ae_fnum
		    && (win->w_buffer->b_ffname == NULL
			 || !(fullpathcmp(
				 alist_name(&WARGLIST(win)[win->w_arg_idx]),
			  win->w_buffer->b_ffname, TRUE, TRUE) & FPC_SAME))));
}