This plugin allows you evaluate code blocks inside markdown documents.

It attempts to implement the basic functionality of org-mode's evaluating code blocks feature inside Neovim.

This plugin requires Neovim version 0.5+.

Install it with plugin manager:

Plug 'jubnzv/mdeval.nvim'

Add the following line in your init.lua:

require 'mdeval'.setup()

You should also enable syntax highlighting inside code blocks in markdown using the built-in functionality. Please define a list of markdown fenced languages in your configuration file:

vim.g.markdown_fenced_languages = {'python', 'cpp'}

To use this plugin, you should move cursor inside a fenced code block with language identifier and execute the :MdEval command. mdeval.nvim will capture the results of the code block execution and inserts them in the markdown file, right after the code block.

You can configure mdeval.nvim by running the mdeval.setup function.

Here is an example:

require 'mdeval'.setup({
  -- Don't ask before executing code blocks
  require_confirmation=false,
  -- Change code blocks evaluation options.
  eval_options = {
    -- Set custom configuration for C++
    cpp = {
      command = {"clang++", "-std=c++20", "-O0"},
    },
    -- Add new configuration for Crystal
    crystal = {
      command = {"crystal"},        -- Command to run interpreter
      language_code = "crystal",    -- Markdown language code
      exec_type = "interpreted",    -- compiled or interpreted
      extension = "cr",             -- File extension for temporary files
    },
  },
})

By default, the plugin will ask your confirmation before evaluating code. This makes sense, because code evaluation is potentially harm operation. You can disable this feature setting require_confirmation option to false, or allow to execute code blocks without confirmation only for some languages, using allowed_file_types option, for example: allowed_file_types={'rust', 'haskell'}.

Probably, it will be a good idea to define keybindings to call :MdEval. This plugin doesn't add default keybindings, but you can do this in your configuration file, for example:

vim.api.nvim_set_keymap('n', '<leader>c',
                        "<cmd>lua require 'mdeval'.eval_code_block()<CR>",
                        {silent = true, noremap = true})

See the complete list of options in the documentation.