Saving is Obsolete: Etherpad adds time slider

http://etherpad.com/ep/blog/posts/saving-is-obsolete

by PStamatiou • 17 years ago

139 68 17 years ago

PStamatiou2• 17 years ago

Just noticed it in my account. Pretty slick! For those wondering what this is - PG used an early version of this to show his essays as he wrote them.

Example from notes I took during an interview with Marcus Nelson of Uservoice. https://pstam.etherpad.com/ep/pad/view/ro.XF6No8LU/rev.1087

darkxanthos3• 17 years ago

So I know this is frowned down upon on HN but fuck it. I've been waiting for this feature ever since the PG essay. I'm extremely excited. Thank you etherpad gods for finally giving me this damn feature! I've been into poetry and essay writing lately and something like this will add a ton of creative expressive value to my writing.

acangiano3• 17 years ago

I want this feature in my code editor. :)

tetha• 17 years ago

My development enviroment has this, 's called git diff and git log?

acangiano3• 17 years ago

Not quite the same thing.

iamwil2• 17 years ago

Sure, developers have this sort of power. Lay people don't. Their target audience is more than just devs.

darkxanthos3• 17 years ago

I can't remember the last time I ever cared for more than just the previous revision lol... this would be WAY overkill (for me at least)

anigbrowl2• 17 years ago

I can see it being a big plus for working on longer-form documents. I write screenplays and when you've got 100 pages going back to look at old autosaves becomes a real pain.

iamwil2• 17 years ago

Depends on your style of writing. Maybe we don't only because we don't delete enough. And maybe we don't delete enough because we didn't have the tools to let us bring up any revision before.

lu• 17 years ago

In vim this is called :earlier.

byrneseyeview• 17 years ago

C-/

bokchoi• 17 years ago

IntelliJ has it. It's called local history:

http://www.jetbrains.com/idea/features/local_history.html

PStamatiou2• 17 years ago

Now if only the PNE version was the same version as what etherpad.com gives you...

mcormier• 17 years ago

Obviously there is a trade off on file size here. I'm curious on how the implementation works.

jules• 17 years ago

Text files are small. Even if they saved every keystroke and you type 100 chars/second for 10 hours it's less than 3.5 megabytes.

yan3• 17 years ago

Not to mention bzip or gzip compresses text like its cotton candy.

steerpike• 17 years ago

I'm incredibly curious as to implementation too. Any of the HN boffins want to breakdown how something like this works?

joe_the_user2• 17 years ago

The source code of Scintilla shows a good implementation of undo functionality. The only thing you'd need only you have undo was a way to serialize and unserialize the information.

yan3• 17 years ago

Can anyone speculate on at least the class of algorithms they are using?

mitko• 17 years ago

I wouldn't be efficient wrt space to keep copy of every version of the file. Instead I suppose they keep the actions of the writer(s).

Algorithmically it shouldn't be complicated. Maybe they just keep history of what happened in the environment and reproduce it. Maybe they even have some checkpoints saved so that there is no need to reconstruct it from the beginning every time. And maybe they can compress events. Instead of: (type a),(type s),(type k) they have just (type ask) and in case you want better granularity they have it recorded somewhere.

yan3• 17 years ago

I was thinking they're using something like video encoders, where differential changes are stored and every N frames (updates? characters?) it stores a copy of the file again for faster tracking and updating.

wwalker32• 17 years ago

Probably the same as a normal text undo. You store the "actions" the user performs against the document on a stack. Each action is a replacement of one text string in the document with another (where strings can be zero-length and can start and end at any point).

Actions can "do" and "undo" themselves against the document trivially. Then to save space, you compress adjacent actions into single actions (e.g. add('a', 0) and add('b', 1) compress to add("ab", 0)).

nazgulnarsil• 17 years ago

I was initially wonder how etherpad could be useful...now I know.

adamhowell• 17 years ago

Some constructive criticism about the screencast, because the dry smacking of your mouth while you're talking is really hard to ignore.

Drink more water between takes, of course, but also try slicing up a granny apple and having a few bites before and during (that supposedly helps your mouth toe the line b/n too wet and too dry).

aaroniba• 17 years ago

Thanks for the feedback, will keep that in mind for next time!

Pistos22• 17 years ago

So does this feature handle history branching and merging? Or are all revisions in one single linear history?

aplusbi• 17 years ago

Sounds like Vim's :later and :earlier commands.

barrkel• 17 years ago

I find myself wondering about trees: what happens if you "slide" back in time, then create a "new timeline" from that point in the history? Does it get appended to the current timeline?

Is it all strictly online? If it also works offline on the client, how does it deal with synchronizing multiple "timelines" created by copying the saved file?

mcav• 17 years ago

It looks like it only lets you browse history linearly, rather than edit and branch. (If you can, it isn't immediately obvious.)

They say "With our new Time-Slider, you can browse the complete history of a document using a familiar user interface." (emphasis mine) It says nothing about editing.

moserware• 17 years ago

Right. You could effectively create a new git revision for the document on each keystroke and then allow branching/merging, but the UI would be challenging and probably not worth the effort.

Raphael• 17 years ago

Select all; past into a new pad; done.

joe_the_user2• 17 years ago

The nice way would be to have this work complete independently of undo, so an undo and edit would look like further edits to the machine.

But it seem unlikely the edits you did last week between revision 2.3 and revision 2.4 would especially interesting to look at. Perhaps yesterday's edits would useful...

What I would like would be an editor which would go-back only on a given selection (cutting and pasting would make implementing such a feature hard but git because clever things...).

thorax2• 17 years ago

This is actually what I've always wanted in a browser. An intuitive way to do Back/Forward that handles multiple branches. :( I'm really surprised someone hasn't done something good with this in a major browser.

snprbob86• 17 years ago

I haven't tried it, but a quick search turned up this Firefox extension, History Tree: https://addons.mozilla.org/en-US/firefox/addon/13316

chriseppstein• 17 years ago

I came here to say that. When I go back in my browser, I want it to show me the site I was looking at scrolled to where I was scrolled in the tab I was looking at.

kingsley_20• 17 years ago

I always thought http://www.irider.com/demo/index.htm did this well. Costs money though.

makmanalp• 17 years ago

There is a firefox addon that colors tabs according to which tabs you opened them from, which is not exactly what you want, but still useful nonetheless.

omouse5• 17 years ago

The web browser uses a stack which is why you can't have multiple branches. You can blame that on Tim Berners-Lee or Marc Andersson, I'm not sure which twit set that precedent.

nitrogen• 17 years ago

Vim supports undo trees. In addition to the :earlier and :later commands mentioned elsewhere in the comments, there is the :undolist command which lists the tree, and :undo n which jumps to a numbered point in the undo tree. If only it were easy to take the vim undo implementation and bolt it onto any program...

wwalker32• 17 years ago

Phototoshop has apparently had this feature for some time. They call it "non-linear history". You can go back to earlier revisions, try new things starting from there, then if you don't like it, erase that history path and go back to your first one. You can also "snapshot" your history so points on it have intuitive labels.

They don't display it as a tree, but it's logically identical -- just flattened out into a list form with the inactive branches grayed out.

omouse5• 17 years ago

It's called version control and branching and merging. It's a solved problem.

roc• 17 years ago

for geeks writing code, sure.

but not for hacks writing web content or your mother writing an email.

artost• 17 years ago

There is a text editor called e-texteditor (http://e-texteditor.com) which has this feature, with a nice visualization of the resulting tree.

mattmaroon• 17 years ago

Automatic versioning with an easy interface: I sure wish Word had this.

astine• 17 years ago

How does this differ from 'undo' with a slider bar interface and auto-save?

mbreese• 17 years ago

Functionally, it doesn't. You can get the same effect by repeatedly hitting "undo" until you have a blank screen. Then you can play it back using "redo" until you reach the end.

The big features are the nice GUI for it and the persistence of the history.

This would be like saving each "undo-able" action with the document. Though, you could also do this by using log-style persistence, saving only the accumulated changes and playing them all back to get the final document. I assume thought that their 'bookmarks' are snapshotted complete copies of the document to limit the 'playback' required.

akkartik2• 17 years ago

It gives undo a 'performance art' aspect. Watching PG write is valuable.

cpr• 17 years ago

Interesting--just like the Google Wave feature. ;-)

omouse5• 17 years ago

So automatic version control? Now if only our operating systems would incorporate that...

absconditus• 17 years ago

Time Machine?

omouse5• 17 years ago

not quite teh same

puredemo• 17 years ago

This is still saving. It just saves (onChange).

Saving is Obsolete: Etherpad adds time slider

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