Using :terminal to send code to Scala REPL

neovim_scala_repl.vim

function! OpenREPL()
    if !exists("g:repl_terminal_id")
        botright split enew
        let g:repl_terminal_id = termopen("scala")
    endif
endfunction

function! PasteScala(lines)
    if !exists("g:repl_terminal_id")
        call OpenREPL()
    endif
    let toPaste = substitute(a:lines, "\n", "^M", "g")
    call jobsend(g:repl_terminal_id, add([':paste', toPaste], ''))
endfunction

nmap \to :call OpenREPL()<CR>
nmap \ts :call PasteScala(@")<CR>
nmap \ta ggVGy \| :call PasteScala(@")<CR>
nmap \tl ^v$"*y \| :call PasteScala(@*)<CR>
vnoremap \tv "*y \| :call PasteScala(@*)<CR>