Its a little thing, but i like how you literally don't need to click on any buttons to save / create a new one / etc. I also like how you can create your own customized path to help you remember the link... just type in a new path and start editing, and you now can share that custom URI.

I think its important to create as little friction to usage as possible, and you've done that.

Thanks!! I really appreciate that. I also like the unique URL feature :)

What's cool is that feature was completely intuitive and you didn't need to point it out. Again, a little thing, but the little bit of delight users experience when they "discover" these types of features goes a long way.

I also like the URL feature, but unlike the other person I did not intuitively expect to type in a a random url and have that work. Its not something people typically do. That said, its pretty cool. You should edit your how to use to include that.

The first thing that I loved about this, that drives me crazy on other real-time online editors, is that pressing "tab" actually creates a tabbed space, and doesn't change the active textarea. Nice job!

Any plan on open sourcing the code to do the real-time editing? I would love to use this real-time editing concept in a project I'm working on.

Thanks! It was actually really simple to make with two tools: http://ace.ajax.org and http://www.firebase.com

If you want to chat about building it I'd love to give you any tips - i'm nbashaw@gmail.com

How did you accomplish the real-time text editing? Is there any OT engine that you hacked into Firebase?

Basically on keyup I ship the whole contents of the editor and the cursor position to firebase. I'm also keeping track of all the active connections to a scratchpad document so I know who is typing. Anytime the code changes on the server, it triggers a callback function on each client that will update the contents of the textarea. If someone else is typing, the document is locked so only 1 person can type at a time. This way I can avoid all the potential merge conflicting type things that can happen.

I'm not sure what an OT engine is. What is that?

OT (See: http://en.wikipedia.org/wiki/Operational_transformation) is one of the technology solutions to the problem that you've solved through a locking mechanism.

Not sure what server architecture you're using, but in Node.js there is a pretty amazing package that integrates with ACE called ShareJS (http://sharejs.org/).

Have you experimented with synchronizing cursors at all?

Thanks! I'll have to read up on OT. Our backend is totally hosted by Firebase, other than a simple Sinatra app that generates the unique IDs.

When you say synchronizing cursors, do you mean having multiple cursors (google docs style) or having a single cursor be in the same position for all clients? We are doing the latter, and I wasn't aware it was possible to do the former with ace but I would love to do it if I can

Seems that I can't reply to the child of my sibling comment so I'm replying here.

ACE is quite ridiculously powerful. On its primary implementation (http://c9.io), it supports multiple cursors with concurrent editing.

I've been able to use ShareJS to get concurrent editing working (see: http://plnkr.co/edit/?p=preview&s=HN4933608) but haven't had a chance to display visual cursors for all simultaneous users. I was thinking that I could get that working using Firebase.

Do you know what/how Firebase is doing the realtime updates? Websockets with fallback to flash?

Hi, I'm one of the Firebase engineers working on keeping clients connected.

We use a mix of different methods to maintain a connection. We normally start with our custom long polling implementation and move to websockets when they are available. We do not currently make use of any flash sockets.

Is Firebase open source?

It states so on the sites/GH pages, but could not find pointers to repo [after 2 circle through 5 different pages poiting to each other].

I believe that's it but I'm not sure. I've emailed the firebase founder and he might be able to chime in here

Looks like you've made sure any recursion only goes one deep? (Awesome)

http://scratchpad.io/5mqq98D51P

Every change forces a reload on the iframe. I wonder if there's a way to prevent that.

  <html>
    <body>
      <h1>Heading</h1>
      <iframe width="640" height="480" 
        src="http://scratchpad.io/5mqq98D51P">
      </iframe>
    </body>
  </html>

That has nothing to do with Scratchpad, it's in the spec for HTML frames: "Infinite recursion is prevented. Any frame that attempts to assign as its SRC a URL used by any of its ancestors is treated as if it has no SRC URL at all (basically a blank frame)."

http://www.w3.org/TR/WD-frames-970331

Thats awesome. Also looking at the source, I discovered it's using keymaster.js and firebase.js, which are new to me. And the implementation of scratchpad.io is very simple and elegant. The design is beautiful, and the code (in scratchpad.js) is so simple that it makes for a good tutorial on using firebase and ace.js.

In fact, if anyone else is interested in forking the code and experimenting with it, feel free to fork my plunk and go to town:

http://plnkr.co/edit/49fOC5Mq3bcBysKfdPor?p=preview

(Hope you appreciate the irony of forking scratchpad.io via Plunker. Also, it'd be wicked if Plunker could automatically "fork" html webpages, pull in all the required resources and/or updating path references).

For a first time coder, being able to see your page change live is very helpful in getting to learn HTML and CSS. This is an amazing complement to the book you are writing - nice work Nathan!

Finally....they had something close to this on codecademy, but this is exactly what I need when trying out new stuff!

Thanks!! Glad you enjoy it

Ok, this editor rocks. Nice use of Ace.js.

One of my biggest frustrations with jsfiddle is the crappy coding area (not to mention the default selection of Mootools among others).

Thanks! All it took was the lovely tomorrow_night_eighties.css theme :)

This is really great, especially as a compliment to the learning tools coming to market.

For front-end designers looking for a similar effect within your own text editor and browser window, I can not live without the CodeKit app now. It does a similar real-time effect each time the template files are saved. Also supports less, js debugging/minification, and other production processes.

http://incident57.com/codekit/

Slightly off topic: You use "enough to be dangerous" with a positive meaning, as in enough to make a real difference in the world, while Alexander Pope quote you use is probably negative: "A little learning is a dangerous thing." as in, someone who knows little can do more harm than good.

Haha this is very true. I like to think of it as an easter egg.

I don't wanna down a nice looking project, very well done on the interface but, another one? There are already like 7+ of these I don't really see the need to produce another one especially one that is HTML+CSS only when many of the others feature JavaScript and more.

What features do you provide that say, http://jsfiddle.net/, http://cssdesk.com/, http://dabblet.com/, http://rendera.heroku.com/, doesn't? (Just the first 4 items that came up in a Google search, the list could go on...)

I think the key extra feature is that you can share what you're working on with someone else and have both people collaborate in real-time (i.e. changes on either end show up near-instantly on the other side). Supplemented by a voice channel, this could potentially be useful.

JSFiddle et. al. don't have this, but I'm sure there are others out there that do.

plunker does have that : http://plnkr.co

Because none of them are the right solution for every use case. http://cssdeck.com/ comes closest but OP's solution is much more simple and to-the-point.

Have the realtime plus: http://jsfiddle.net/ And you will rock!

Right now, you are just awesome ;).

Just so happen to have a solution for you: http://plnkr.co/edit/?p=streamer

DEMO: http://plnkr.co/edit/?p=preview&s=HN4933608

This is perfect - love the immediate feedback for my own prototyping.

Could probably use the multi-user sync for front-end technical interviews.

^Exactly what I was thinking.

Oh man this is incredible - I want to find a way to embed this into Emacs, this is so useful.

You can modify Emacs so that it does something on every change in the current buffer, like for example save the change to disk if it's a file-backed buffer.

You could then have a script refreshing the browser on every file change (do it from outside Emacs, calling shell scripts from Emacs or anything 'non-Emacsy' from Emacs is too slow for the usecase here).

However you'll probably have to find a way for the 'save file on every buffer modification' to be very fast otherwise it's going to annoy you and prove impractical.

Btw I can't wait for someone to implement at least part of Emacs in JavaScript so that, eventually, users used to Emacs shall have the possibility to have a Web text editor that doesn't s*ck. Maybe using ClojureScript + the implementation of Emacs redone in Clojure (I think there's a project trying to do that right now).

Great work. (love things that are "clean")

    Press ⌘ + i to toggle fullscreen view

I don't have this key and suspect a lot of others don't either. ;)

I just realized that after HNing it :( Terrible oversight. However, the tooltip when you hover over the arrow button is OS-appropriate https://gist.github.com/4321208#file-scratchpad-js-L344

This is awesome! I constantly look for live editors but haven't found a good one for front-end. I tried Adobe Brackets, Firebug (for in-window editing) but all had their complexities and constraints. Scrathpad.io is by far the most intuitive and best one for HTML and CSS out there!

Have you tried Plunker (http://plnkr.co/edit/?p=streamer)? DEMO: http://plnkr.co/edit/?p=preview&s=HN4933608

Not to detract from what is a pretty cool project, and I hope OP had fun making it, but: http://codepen.io is this and quite a bit more. It supports HTML+JS+CSS as well as e.g. Jade, SASS and CoffeeScript- if that's what floats your boat- and some nice social features, like featured pens and saving to Gists.

Other commenters have pointed out a myriad of similar such services. I'm surprised Codepen hasn't come up already.

@brycecolquitt, you are obviously very talented, and I look forward to whatever you come up with in the future. I just hope it's not in a space as hotly contested as this.

Thanks, but this was actually made by my friend Nathan Bashaw (nbashaw). I just submitted it because I think it's awesome :) I think the tool is great for a certain group of people: beginners and front-end folks who want to quickly see what something looks like or do some debugging.

I'm not sure if codepen supports the realtime google-docs-style collaboration, either, which Scratchpad is good for. It's simple product with no superfluous features.

Yeah but it's nowhere near as nice to edit with. The textarea's are short, the content frame is short... I think this is a case where simplicity wins out.

SASS would be a cool feature though.. (as long as it came with Compass)

Very nice. Love the responsiveness and good use of (OS-aware?) keyboard shortcuts.

Bug: (Chrome Version 23.0.1271.97 on OSX)

Expand the side panel and select a document from the RECENT list. The editor area doesn't update completely; the text loads, but there are only line numbers up to the length of the previously viewed document and it's impossible to move the cursor below the last line number (http://i.imgur.com/h9nMh.png).

EDIT: Correction, the line numbering is correct, the problem is with the line-height in the editor.

Whoa! Thanks for sending this in! Crazy bug.

Absolutely amazing. A couple things that bother me, and they might just be from Ace.js:

When typing text into a <p> or an <h1> for example, if I type "I'm", I get the smart double quote feature, and end up typing:

I'm going to the zoo'

Likewise, if I go back into the stream of some text in a <p>, and want to wrap it in a span, if I click at the start of it and type <span id="foo">, I get another span on the other side of my cursor, pushing the existing text over.

Otherwise, utterly fantastic tool. Trying to use it for real work already :)

Thanks so much, Scott! That is indeed an ace default, but I can try and figure out how to override it. Syntax completion is always tricky.

Pretty nice, I'll probably be using this for debugging and examples.

Bug:

Open the about panel by clicking the icon in top left (three horizontal bars). Close the panel by clicking the same icon.

Maximize the preview window by clicking the arrow in the top right of the edit panel. Click the arrow to view the code panel again.

The about panel pops out as well and the arrow button covers the show/hide about (three horizontal bars) button. Expected behavior: it should return to the view that I had before maximizing.

Crazy! I thought I encountered this once in development but couldn't repro it again. Thought I was going crazy. Thank you so much!!

Thank you for this! I'm in the process of teaching my brother HTML/CSS, and this is the perfect tool for when he is not sitting next to me.

I would love to be able to work in realtime (a la Etherpad) with someone else - would take pairing to a whole new level. Also, style management could quickly get messy - I know you are trying to keep the UI as simple as possible, but I would love to be able to quickly toggle between HTML and CSS on different tabs (instead of scrolling).

Nicely done on Scratchpad. The interface seems to be the right combination of simple and intuitive. It would be great to see the source code as many others have said.

I'm particularly curious as to how you've done the collaborative bit given that you don't have explicit control over the order of operations of edits.

I would assume realtime editing will be supported by the browser developer tools fairly soon.

Cool! I'm going to use it for debugging.

Quick thing: I have a page quickramen.com/test/test that has links that navigate around the page. If you click those now, it loads the code again in another mini-window and doesn't go anywhere.

JUST a bug to be aware of if you're keeping a log!

I'm building a similar one (it also allows you to inspect html elements like using Firebug or Webkit's Dev tools), and it's a native Windows app (and really fast one!) http://liveditor.com

"Press ⌘ + i to toggle fullscreen view"

What is this thing, I don't have such a key on my computer?

It's on Mac keyboard, on a not-Apple system it's Ctrl+i

Suggestion for the OP, maybe it's better to add it to your page (not everybody is using Apple computers)

How is this different from codemirror? Codemirror's preview utility easily handles this (and much more versatile in other ways):

  http://codemirror.net/
  http://codemirror.net/demo/preview.html

Nice work and all, but what's wrong with a local .html file your favorite text editor, and a browser? I've been doing that for years to play around with html, css, and js.

I wanted to reduce this:

1. Create a file 2. Open it in your text editor 3. Edit code 4. Switch to browser 5. Open up the file 6. Switch back to editor 7. Edit code 8. Hit save 9. Switch back to browser 10. Hit refresh 11. GOTO 6

to this:

1. Go to http://scratchpad.io 2. Write code

I use Livejs for the same effect, but this is much smoother obviously since it can trigger on key press rather than polling the resource constantly from the web page.

Seems very slow in firefox, can't keep up with my typing and missed the characters inbetween.

Not sure if it's supposed to just say 'Loading...' at the top the whole time either..

Sinatra.io does something similar, also built on Firbase. I believe their code is on github if anyone is interested in implementation.

Sinatra.io seems to be down? Do you know their github address?

Really nice execution on this. So simple and just what I'd want if I was just starting to learn how to code. Bravo.

Beautiful. Love the fact that out of habit I pressed Cmd+D to delete the line and it worked :) Nice work

What would it take to implement javascript? Is it merely trivial, or was it left out for security?

Really cool, kinda like brackets.io, but online!

Is there anyway to make the text editor pane resizeable?

I could definitely make a drag-to-resize thing, but I opted against it in V1 for simplicity's sake. We do have a fullscreen mode though

Will you be able to make new projects and make them private?

It'd be great if the command tip wasn't only for Mac btw

Ah good call! It's control + i in mac

Very impressive. Love the dark color scheme.

LESS/SASS possible? :)

It's definitely a possibility! Actually, more like a probability. Just didn't want to build too much into V1

dear scratchpad: http://scratchpad.io/j2la3taRYW#fullscreen

Haha thanks so much!! That is awesome

Would like the option to import a url to edit.

it will be great if we can pick some templates like bootstrap and start coding right away from the application.

This is really cool. Nice work

i wish i could adjust the width of the code section. otherwise it's pretty neat.

Get this added to repl.it

very cool!