add summary to readme

README.md

@@ -2,6 +2,63 @@
 
 # Getting started using Lua in Neovim
 
+## Summary
+
+- [Translations](#translations)
+- [Introduction](#introduction)
+  - [Learning Lua](#learning-lua)
+  - [Existing tutorials for writing Lua in Neovim](#existing-tutorials-for-writing-lua-in-neovim)
+  - [Companion plugins](#companion-plugins)
+- [Where to put Lua files](#where-to-put-lua-files)
+  - [init.lua](#initlua)
+  - [Modules](#modules)
+  - [Runtime files](#runtime-files)
+- [Using Lua from Vimscript](#using-lua-from-vimscript)
+  - [:lua](#lua)
+  - [:luado](#luado)
+- [Sourcing Lua files](#sourcing-lua-files)
+  - [Sourcing a lua file vs calling require()](#sourcing-a-lua-file-vs-calling-require)
+  - [luaeval()](#luaeval)
+  - [v:lua](#vlua)
+  - [Tips](#tips-2)
+- [The vim namespace](#the-vim-namespace)
+  - [Tips](#tips-3)
+- [Using Vimscript from Lua](#using-vimscript-from-lua)
+  - [vim.api.nvim_eval()](#vimapinvim_eval)
+  - [vim.api.nvim_exec()](#vimapinvim_exec)
+  - [vim.api.nvim_command()](#vimapinvim_command)
+  - [vim.cmd()](#vimcmd)
+  - [vim.api.nvim_replace_termcodes()](#vimapinvim_replace_termcodes)
+- [Managing vim options](#managing-vim-options)
+  - [Using api functions](#using-api-functions)
+  - [Using meta-accessors](#using-meta-accessors)
+- [Managing vim internal variables](#managing-vim-internal-variables)
+  - [Using api functions](#using-api-functions-1)
+  - [Using meta-accessors](#using-meta-accessors-1)
+- [Calling Vimscript functions](#calling-vimscript-functions)
+  - [vim.fn.{function}()](#vimfnfunction)
+- [Defining mappings](#defining-mappings)
+  - [API functions](#api-functions)
+  - [vim.keymap](#vim.keymap)
+- [Defining user commands](#defining-user-commands)
+  - [Caveats](#caveats-5)
+- [Defining autocommands](#defining-autocommands)
+- [Defining highlights](#defining-highlights)
+- [General tips and recommendations](#general-tips-and-recommendations)
+  - [Reloading cached modules](#reloading-cached-modules)
+  - [Don't pad Lua strings!](#dont-pad-lua-strings)
+  - [Notes about Vimscript <-> Lua type conversion](#notes-about-vimscript---lua-type-conversion)
+  - [Setting up linters/language servers](#setting-up-linterslanguage-servers)
+  - [Debugging Lua code](#debugging-lua-code)
+  - [Debugging Lua mappings/commands/autocommands](#debugging-lua-mappingscommandsautocommands)
+  - [Testing Lua code](#testing-lua-code)
+  - [Using Luarocks packages](#using-luarocks-packages)
+- [Miscellaneous](#miscellaneous)
+  - [vim.loop](#vimloop)
+  - [vim.lsp](#vimlsp)
+  - [vim.treesitter](#vimtreesitter)
+  - [Transpilers](#transpilers)
+
 ## Translations
 
 - [:cn: Chinese version](https://github.com/glepnir/nvim-lua-guide-zh)