Ripple

This thin plugin makes it easy to send code to a REPL (read-evaluate-print loop) running within vim or nvim. Some advantages of this plugin over some of the alternatives (such as iron.nvim) are the following:

• This plugin is written and can be configured fully in viml.

• The cursor does not move when a code chunk is sent to the REPL.

• If vim-highlightedyank is installed, motions sent to the REPL are highlighted.

• If not explicitly opened by y<cr>, the REPL opens automatically once a code chunk is sent.

• The plugin is compatible with Tim Pope's vim-repeat.

• Previous code selections are saved and can be reused easily (see yp in the documentation).

(Click to enlarge.)

Installation

Using vim-plug:

Plug 'urbainvaes/vim-ripple'

" OPTIONAL DEPENDENCIES

" Highlight code chunks sent to REPL
Plug 'machakann/vim-highlightedyank'

" Streamline navigation (e.g. autoinsert in terminal)
Plug 'urbainvaes/vim-tmux-pilot'

Configuration of the REPLs

New REPLs can be defined in the dictionary g:ripple_repls. These definitions take precedence over the default REPLs defined in the plugin, which are listed below. In the dictionary, the keys are filetypes and the values are dictionaries specifying options of the REPL. The entries that each of these dictionaries can contain are given in the following table:

Keys	Default values (except for Python)	Description
command	Mandatory argument	String
pre	""	String
post	""	String
addcr	0	Boolean (0 or 1)
filter	{x -> x} (no effect)	0 or a function reference

• The mandatory key command contains the command to start the REPL (e.g. julia, guile, bash).

• The parameters pre and post contain strings to prepend and append to code sent to the REPL, respectively. This is sometimes necessary to enable sending several lines of code to the REPL at once (see Python example below).

• The parameter addcr controls whether an additional <cr> should be appended to the code chunks that are followed by a blank line. (This can be useful to avoid the need to press <cr> manually in the terminal window. In ipython, for example, two <cr> are required to run an indented block.)

• Finally, the parameter filter is a function employed to format the code before sending it to the REPL. For example, this is used in the default settings for removing comments from zsh code chunks, which is useful because comments are not allowed in interactive shells by default (this can be changed using setopt interactivecomments).

The default configuration for python can be reproduced by the following lines in .vimrc:

let g:ripple_repls = {}
let g:ripple_repls["python"] = {
    \ "command": "ipython",
    \ "pre": "\<c-u>\<esc>[200~",
    \ "post": "\<esc>[201~",
    \ "addcr": 1,
    \ },

If one wishes the plugin to work with indented code, for example in a main() function, one may add a filter as follows :

function! Remove_leading_whitespaces(code)
    " Check if the first line is indented
    let leading_spaces = matchstr(a:code, '^\s\+')

    if leading_spaces == ""
        return a:code
    endif

    " Calculate indentation
    let indentation = strlen(leading_spaces)

    " Remove further indentations
    return substitute(a:code, '\(^\|\r\zs\)\s\{'.indentation.'}', "", "g")
endfunction

" Add filter to REPL configuration
let g:ripple_repls["python"]["filter"] = function('Remove_leading_whitespaces')

This filter is not enabled by default, but it is implemented in the plugin by the function ripple#remove_leading_whitespaces, which you can use in the REPL configuration. Currently only the following languages have default configurations: Python, Julia, Lua, R, Ruby, Scheme, Sh and Zsh. Feel free to open a pull request to add support for other languages.

Mappings

The functions are exposed via <Plug> mappings. If g:ripple_enable_mappings is set to 1, then additional mappings to keys are defined as follows:

<Plug> Mapping	Default key mapping	Description
<Plug>(ripple_open_repl)	y<cr> (nmap)	Open REPL
<Plug>(ripple_send_motion)	yr (nmap)	Send motion to REPL
<Plug>(ripple_send_previous)	yp (nmap)	Resend previous code selection
<Plug>(ripple_send_selection)	R (xmap)	Send selection to REPL
<Plug>(ripple_send_line)	yrr (nmap)	Send line to REPL
<Plug>(ripple_send_buffer)	yr<cr> (nmap)	Send whole buffer to REPL

If <Plug>(ripple_send_motion) is issued but no REPL is open, a REPL will open automatically. A mnemonic for yr is you run. Counts and registers can be passed to yp in order to refer to code selections other than the last; see the documentation for details.

Additional customization

Config	Default	Description
g:ripple_winpos	"vertical"	Window position
g:ripple_term_name	undefined	Name of the terminal buffer
g:ripple_enable_mappings	1	Whether to enable default mappings
g:ripple_highlight	"DiffAdd"	Highlight group
g:ripple_always_return	0	Add <cr> even for charwise motions

The options g:ripple_winpos is the modifier to prepend to new (in nvim) or term (in vim) when opening the REPL window. To disable the highlighting of code chunks sent to the REPL, simply let g:ripple_highlight = "". Highlighting works only when the plugin vim-highlightedyank is installed. For more information, see

:help ripple

License

MIT