the first call to `require()` for each module,
with subsequent calls returning the cached value without searching for, or
executing any script. For further details see |require()|.

For example, if 'runtimepath' is `foo,bar` and |package.cpath| was
`./?.so;./?.dll` at startup, `require('mod')` searches these paths in order
and loads the first module found ("first wins"): >
    foo/lua/mod.lua
    foo/lua/mod/init.lua
    bar/lua/mod.lua
    bar/lua/mod/init.lua
    foo/lua/mod.so
    foo/lua/mod.dll
    bar/lua/mod.so
    bar/lua/mod.dll
<
Note:

- Although 'runtimepath' is tracked, Nvim does not track current
  values of |package.path| or |package.cpath|. If you happen to delete some
  paths from there you can set 'runtimepath' to trigger an update: >vim
      let &runtimepath = &runtimepath

- Skipping paths from 'runtimepath' which contain semicolons applies both to
  |package.path| and |package.cpath|. Given that there are some badly written
  plugins using shell, which will not work with paths containing semicolons,
  it is better to not have them in 'runtimepath' at all.

==============================================================================
COMMANDS                                                        *lua-commands*

These commands execute a Lua chunk from either the command line (:lua, :luado)
or a file (:luafile) on the given line [range]. As always in Lua, each chunk
has its own scope (closure), so only global variables are shared between
command calls. The |lua-stdlib| modules, user modules, and anything else on
|package.path| are available.

The Lua print() function redirects its output to the Nvim message area, with
arguments separated by " " (space) instead of "\t" (tab).

                                                                  *:lua=* *:lua*
:lua {chunk}
    Executes Lua chunk {chunk}. If {chunk} starts with "=" the rest of the
    chunk is evaluated as an expression and printed. `:lua =expr` and `:=expr`
    are equivalent to `:lua print(vim.inspect(expr))`.

    Examples: >vim
        :lua vim.api.nvim_command('echo "Hello, Nvim!"')
<    To see the Lua version: >vim
        :lua print(_VERSION)
<    To see the LuaJIT version: >vim
        :lua =jit.version
<
:{range}lua
    Executes buffer lines in {range} as Lua code. Unlike |:source|, this
    always treats the lines as Lua code.

    Example: select the following code and type ":lua<Enter>" to execute it: >lua
        print(string.format(
            'unix time: %s', os.time()))
<
                                                                *:lua-heredoc*
:lua << [trim] [{endmarker}]
{script}
{endmarker}
    Executes Lua script {script} from within Vimscript. You can omit
    [endmarker] after the "<<" and use a dot "." after {script} (similar to
    |:append|, |:insert|). Refer to |:let-heredoc| for more information.

    Example: >vim
        function! CurrentLineInfo()
        lua << EOF
        local linenr = vim.api.nvim_win_get_cursor(0)[1]
        local curline = vim.api.nvim_buf_get_lines(0, linenr - 1, linenr, false)[1]
        print(string.format('Line [%d] has %d bytes', linenr, #curline))
        EOF
        endfunction
<
    Note that the `local` variables will disappear when the block finishes.
    But not globals.

                                                                      *:luado*
:[range]luado {body}
    Executes Lua chunk "function(line, linenr) {body} end" for each buffer
    line in [range], where `line` is the current line text (without <EOL>),
    and `linenr` is the current line number. If the function returns a string
    that becomes the text of the corresponding buffer line. Default [range] is
    the whole file: "1,$".

    Examples: >vim
        :luado return string.format("%s\t%d", line:reverse(), #line)

        :lua require"lpeg"
        :lua -- balanced parenthesis grammar:
        :lua bp = lpeg.P{ "(" * ((1 - lpeg.S"()") + lpeg.V(1))^0 * ")" }
        :luado if bp:match(line) then return "=>\t"