Pipes content of files to a node repl whenever they change and adds many more features to enable a highly interactive coding experience.


Pipes content of files to a node repl whenever they change to enable a highly interactive coding experience.

Adds keymaps, doc access, vim binding and maps and prints highlighted source of functions right in the repl.

Check out the replpad home page for demos and tutorials.

  • watches all *.js files inside root and all subdirectories and sources a file to the repl once it changes
  • access core module docs in the repl via the dox() function that is added to every core function, i.e. fs.readdir.dox()
  • access user module readmes in the repl via the dox() function that is added to every module installed via npm, i.e. marked.dox()
  • access function's highlighted source code, info on where function was defined (file, linenumber) and function comments and/or jsdocs where possible via the src property that is added to every function, i.e. express.logger.src
  • scriptie-talkie support (see .talk command)
  • adds commands and keyboard shortcuts
  • vim key bindings
  • key map support
  • parens matching via match token plugin
  • appends code entered in repl back to file via keyboard shortcut or .append command
  • adjusts __filename, __dirname and require to work for the file that is being sourced
  • ensures sourced code is parsable on a line by line basis before sending to repl by rewriting it
  • exposes module.exports of last sourced file as $
  • exposes the underlying repl as $repl in order to allow further customizations

Table of Contents generated with DocToc

npm install -g replpad
replpad [path/to/root]

If path/to/root is omitted then no files are watched.

Example: replpad . watches current directory and all sub directories.

You can use replpad inside of your application and specify repl start options:

var replpad = require('replpad');
var repl = replpad({
    prompt          :  'my-prompt >'
  , input           :  process.stdin
  , output          :  process.stdout
  , ignoreUndefined :  true
  , useColors       :  true
  , useGlobal       :  true
  , terminal        :  true

Some commands were added to the built in repl commands. Here is a list of all of them:

pad > .help
.append         Appends the last entered parsable chunk of code or the last line to the last file that was sourced in the repl
.clear          Break, and also clear the local context
.compact        [on] Toggles if code is compacted before being sourced to the repl
.depth          [2] Sets the depth to which an object is traversed when printed to the repl
.exit           Exit the repl
.help           Show this list of repl commands
.hidden         [off] Set whether hidden properties are included during traversal of an object that is printed to the
.highlight      [off] Toggles if syntax highlighted code is printed to the repl before being sourced
.load           Load JS from a file into the REPL session
.pack           Load your package.json dependencies and devDependencies into the repl context
.save           Save all evaluated commands in this REPL session to a file

Note: commands that toggle a setting like .compact take a second parameter: on|off. If it is ommitted the state is toggled, i.e if it was on it is turned off and vice versa.

Note: when code is syntax highlighted, it is still followed by the compacted code which is necessary in order to have the repl evaluate it.

You can add commands to the repl in real time via $repl.defineCommand

$repl.define('sayhi', { 
    help: 'Says hi via .sayhi'
  , actionfunction () { console.log('Hi!') }
  • Ctrl-L clears the terminal
  • Ctrl-D exits replpad
  • Ctrl-A Appends the last entered parsable chunk of code or the last line to the last file that was sourced in the repl.

When the .append command or the append keyboard shortcut is executed, replpad will attempt to find a parsable chunk of code to append. If the last line is parsable or no parsable chunk is found, it will append the last line.


Assume we entered:

2 + 3
function foo() {
  var a = 2;
  return a;

The first valid JavaScript are the last 4 lines combined. Therefore the entire function foo will be appended. This is makes more sense than appending just } for instance.

Additionally the code is reformatted with 2 space indents.

Plugins can be enabled/disabled in the lower portion of the replpad config file (default.

The following plugins are available.

If enabled, a subset of vim bindings are added to replpad via readline-vim.

Consult its readme for available vim bindings.

replpad allows you to specify keymaps.

imap is used to map keys in insert mode and nmap to map keys in normal mode.

// map 'ctrl-t' to 'esc', allowing to switch to normal mode via 'ctrl-t' 
$repl.imap('ctrl-t', 'esc'); 
// go forward in history via 'ctrl-space' in normal mode 
$repl.nmap('ctrl-space', 'j')

You can list all registered mappings via: $repl.maps.

These are handled by readline-vim, so in order to learn more please read this section.

You can also declare mappings to be applied at startup by including them inside the map section of your config file as explained in configuring replpad.

Mappings are limited by what the underlying nodejs readline supports. Consult this section for more information.

In general I found that only a few mappings in normal mode have the desired effect. In insert mode things are somewhat better.

If enabled, it will match parens, braces, brackets and quotes by jumping the cursor to the matching token emacs style.

  • in order to auto update your file whenever you append a repl line to it, you need to :set autoread
  • in case you are using terminal vim, autoread is not working great, so you should add the WatchFile script to your vim configuration

replpad is fully configurable.

When launched for the first time it creates a config file at ~/.config/replpad/config.js. Initially this is a copy of the default-config, but you can edit it to change these defaults.

Reading the comments in that file should give you enough information to tweak it.

  • more vim bindings
  • only pipe part of a file enclosed by start/stop comments
  • pause/resume feeding files via command
  • list an object's properties by type (i.e. Function, Object, String)