Convenience in the Haskell ecosystem

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This is one of the reason why I have given up on using external tools and haven’t even try HLS. I rely instead on little knows ghci commands :type-at, :uses and :loc-at.
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I believe those commands has been merged from intero, leading to intero to be obsolete.
However, they are a bit tricky to call manualy but are easily to integrate in a text editor.

I use vim and tmux to load ghci and send command from vim to (via tmux) ghci.

Here is the code vim code to transform a visual selection to a ghci command

vnoremap <space>rt :call Haskell_type_at("type-at")<CR>gv
vnoremap <space>ru :call Haskell_type_at("uses")<CR>gv
vnoremap <space>rl :call Haskell_type_at("loc-at")<CR>gv
nmap <space>rT viw<space>rtv
nmap <space>rU viw<space>ruv
nmap <space>rL viw<space>rlv

function Haskell_type_at(mode) range
  " mode can be type-at uses loc-at
  let l:command = printf (":%s %s %d %d %d %d\n",a:mode,  expand("%:p"), line('.'), col("'<"), line("'>"), col("'>")+1)
  call TmuxSend(l:command)
endfunction
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