How to enable horizontal scrollbar to pop when ‘nowrap’ is set in Vim?

Question

Can someone help me to find a solution for the following inconvenience? I would like horizontal scrollbar to appear whenever I set the nowrap option, and vice versa when I set it back to wrap.

Currently I use these settings individually to ease my work:

nnoremap <silent> <F3> :if &guioptions=~#'b'<Bar>set guioptions-=b<Bar>else<Bar>set guioptions+=b<Bar>endif<CR> map <F2> :set nowrap! <CR>  

Is there a way to toggle them both at the same time, in concordance?

Answer 1

Let us construct a single command for switching both options accordingly at once. First of all, it should toggle the wrap option anyway:

:set wrap! 

Then, guioptions should be changed depending on whether wrapping is enabled at the moment of command's execution. If text is wrapped, the bottom scrollbar should be shown in preparation for wrap to be disabled:

:set guioptions+=b 

Alternatively, if text wrapping is turned off, it should hide the bottom scrollbar:

:set guioptions-=b 

In order to make one command out of the above three, we can use the expression mapping

:nnoremap <silent><expr> <f2> ':set wrap! go'.'-+'[&wrap]."=b\r" 

which turns into the sequence of keystrokes

:set wrap! go+=bEnter

when the wrap option is set (and evaluates to one), or into

:set wrap! go-=bEnter

otherwise (when &wrap evaluates to zero).