Using scnvim from lua

Using scnvim from lua

SCNvim exposes some really handy functions that allows you to execute SuperCollider code from keymappings or your settings to create your own hacks.

scnvim.send

send is for sending SuperCollider code from Nvim to sclang without getting any feedback into Nvim again. This version posts things to the post window.

lua << EOF
-- Play a sine wave
local code = [[play{SinOsc.ar(110)}]]
require'scnvim'.send(code)
EOF

send_silent is a function equivalent to the above but it does not post to the post window when called.

scnvim.eval

eval allows the user to evaluate SuperCollider code and get the return value inside of lua and use it for something useful.

An example that asks the server how many output channels it's got and prints it in Nvim:

lua << EOF
-- Code to be evaluated
local supercollider_code = [[s.options.numOutputBusChannels]]

-- This function will be called with the return value of the supercollider code above
local callback = function (returnVal) print("SuperCollider server has " .. returnVal .. " channels") end

require'scnvim'.eval(supercollider_code, callback)
EOF

Using the functions in a keymap

lua << EOF
-- SuperCollider code. Note: double quotes need to be escaped like below
local sc_code = [[play{SinOsc.ar(110) * 0.1]]

-- Normal mode mapping
local opts = { nowait = true, noremap = true, silent = false }
local lhs = "<F11>" -- The key to be mapped
-- The thing that will be executed by said key:
local rhs = string.format("<cmd> lua require'scnvim'.send('%s')<cr>", sc_code)
vim.api.nvim_buf_set_keymap(0, "n", lhs, rhs, opts)
EOF

Mapping multi line expressions

If you want to easily add multi line code in mappings, you can use :gsub like below to clean it up:

lua << EOF
-- Normal mode mapping
local opts = { nowait = true, noremap = true, silent = false }

local sc_code = [[
play {
  SinOsc.ar(440) * 0.1;
};
]]
local lhs = "<F11>" -- The key to be mapped
local rhs = string.format("<cmd> lua require'scnvim'.send('%s')<cr>", sc_code:gsub('\n', ''))

vim.api.nvim_buf_set_keymap(0, "n", lhs, rhs, opts)

EOF