Tern – Intelligent JavaScript editing

http://ternjs.net/

by aerique • 13 years ago

191 79 13 years ago

ternjs.net

dotmanish• 13 years ago

I typed "[[[[" and the script became unresponsive (hung).

Repeated by reloading the page. Same result.

FireFox / MacOS.

marijn19• 13 years ago

That's bad. I'll look into it right away.

adlpz3• 13 years ago

Working fine on Chrome 24 on Linux/x64.

marijn19• 13 years ago

Should be better now. It was a change I made half an hour ago. Ad-hoc changes to sites that are receiving traffic always do that.

[You'll need to hard-refresh to get the fixed code.]

adlpz3• 13 years ago

Well, that looks really nice. I am not a IDE type, but I do enjoy nice coding helpers when I write. This, well integrated into say, Vim, would make Javascript programming really comfortable.

3ds• 13 years ago

upvote for vim bindings, that would totally rock!

thadk• 13 years ago

The cloud9 ide's open source javascript-based editor, [Ace](http://ace.ajax.org/build/kitchen-sink.html) can mimic vim mode.

Though ternjs's developer created CodeMirror, the platform would be agnostic of editor and could easily be ported to that.

jakozaur• 13 years ago

Amazing, but it could be even more awesome if you could provide API that could be integrated with other editors.

NuZZ• 13 years ago

> But that is a proprietary system tied to a single IDE. If the crowd-funding succeeds, Tern will be an open system that can (and will) be plugged into a variety of editors and IDEs.

Hopefully, that will happen. Sounds very cool though, as my IDE, sublime text, is rather underpowered in the intelligence department I'm afraid.

I could imagine it applying .tmLanguage scopes to words in the document, where you could colorize different variables according to type (I would opt for different background shades, myself). Then, mixed type colors (prompting you to click it and see what Tern says) when you can't know. Damn, that would be helpful.

marijn19• 13 years ago

As NuZZ noted, this is the plan. It is already written as a library with a server-like architecture (you send requests and get JSON responses). The vision is to wrap it in a stand-alone HTTP server shim that understands .tern-project files that you can drop in your project directory, and then write editor plug-ins that talk to this server (and automatically start it up if it's not already running).

V1• 13 years ago

Backed. Like everybody who touches JavaScript should do. Also. mmmm finally decent vim bindings for javascript?

I do wonder how it will compare to Eclipse Orion's JavaScript content assist which is using Esprima as parser.

http://contraptionsforprogramming.blogspot.nl/2012/02/better...

marijn19• 13 years ago

(I'm the author of Tern -- I'm obviously biased.)

It compares very favorably. The Orion approach, as I understand it (I only did some quick messing around with scripted, am not an expert) is very local, whereas Tern tries to do whole-program analysis. This should allow it to pick up much more information.

visarga2• 13 years ago

Is it able to track all dependencies in a web page for autocomplete? I mean, keywords defined in dependent files - do they automagically work?

gngeal2• 13 years ago

"whereas Tern tries to do whole-program analysis."

I suppose you're not doing live type feedback? Given a test suite for the code being edited, that would seem like a natural thing to do.

cromwellian2• 13 years ago

I find most of these attempts to code-completion in JS to be annoying, like bad speech recognition, if the accuracy is poor, it becomes frustrating. Not to knock their attempt, but I find that if codeassist isn't like 98% accurate, it often becomes more work to step through all of the wrong entries and not find what I want, then to just type it out.

The closest I've seen to something that works well is IntelliJ IDEA 12, when working with ActionScript, Closure annotated JS (JsDoc'ed libraries), or by comparison, the Dart editor.

With IntelliJ 12, if you're looking at a library with enough JsDoc on functions, the type inferencing seems to be a lot more accurate. Find Usages, Go to Definition, code-assist, all seem to be more pleasurable to use.

I don't like Flash, but ActionScript3 in IntelliJ is as close to the Java/C#/et al experience you'll get with respect to accuracy of assist. Probably wouldn't hard to port this over to JSX or Typescript which have similar syntax.

marijn19• 13 years ago

If you're using completion to verify that a thing has the type you thought it has, then yes, Tern won't help you much. If you're using it to save keystrokes, it certainly will.

Slightly related, I'm working on a feature where it distinguishes wild guesses from probably correct information by showing a different icon in the completion list.

visarga2• 13 years ago

Another way to go about it would be to mark the keywords that seem mistyped or auto-correct them. That would be less intrusive for people who don't want to select from drop downs.

larve2• 13 years ago

I love autocompletion (even when it is half working, like intellij when the inheritance marking annotations don't always follow through, my cleverly optimized jsdoc markup for backbone and co broke down when switching to idea12). It saves me so much time looking stuff up and APIs, and if it can indicate the number and name of arguments required, i usually don't have to use the docs anymore.

And M-./find usages is very useful too, even when it is not perfect.

I pledged, and hope you will get enough funds together.

Erwin• 13 years ago

The newest PyCharm uses an interesting dynamic approach. You can run your app in their debugger and enable collecting of type parameter info (at a significant performance loss, however).

So when you have a function like: def foobarize(f): return f.something *2; then it will know what types f might have when foobarize is called. Now when you go back into the editor, it can give you a hint about it.

Other than that, it uses some type hints from docstrings (you can tell it type foo is YourClass and it will complete based on that) and light type guessing.

kodablah• 13 years ago

I disagree, I believe TypeScript/VisualStudio provides a closer experience than AS/IntelliJ. The inference and refactoring work quite well. And they are in their infancy, generics are coming very soon.

cromwellian2• 13 years ago

Can you give an example of where AS/IJ fail and TS/VS succeeds? IntelliJ's started supporting TS recently and will likely improve. Their whole brand is multilanguage support and they support more languages than any other IDEA. For example, WebStorm 6 added TypeScript, CoffeeScript, and Dart.

kayoone3• 13 years ago

It might sound like an abomination, but Visual Studio is apart from obv. being excellent in C++/C# also a very pleasant IDE for Javascript, Python or even PHP!

In fact i have been an "texteditor-only" type in the past, but coding C# in Visual Studio has really been a revelation for me.

marijn19• 13 years ago

I know. I was blown away by VS when I was researching what others were doing in this space. Their approach is also very clever -- there's an interesting talk about it at http://channel9.msdn.com/Events/TechEd/NorthAmerica/2012/DEV...

gruseom2• 13 years ago

Care to mention what you found clever in their approach?

gngeal2• 13 years ago

"In fact i have been an "texteditor-only" type in the past, but coding C# in Visual Studio has really been a revelation for me."

The fact that application X is "just a text editor" is not a justification for X having poor editing functions. In fact, you'd expect a specialized text editor to have better editing functions that an IDE, since an IDE can have other selling points, such as an integrated build system, a version manager, a profiler or a debugger, whereas an editor can only impress you solely by its usability for...well, editing.

kayoone3• 13 years ago

Yep you are right, i meant this more in a way of working style. In the past i thought its the best approach to only use a text editor and do everything by hand, know your Code, work like a pro etc. But just simple things in VS like "Jump to Definition" or "Find Usages" combined with powerful IntelliSense and Refactoring functions is such a joy to use. I didnt even talk about the debugging tools, but well i am an IDE guy now, at least for large projects.

vukmir• 13 years ago

I think that anybody who works with JS should support this project and its author (Marijn Haverbeke of the Eloquent JavaScript fame.)

P.S. Works fine on Chromium Version 24.0.1312.56 Ubuntu 12.04 x64

meryn• 13 years ago

Looks cool! How do you gauge the difficulty of adding support for CoffeeScript to this?

Re the indiegogo campaign: I think you should consider adding an extra supporter tier between 25 USD and 1000 USD. The 200 USD tier of CoffeeScript Redux http://www.kickstarter.com/projects/michaelficarra/make-a-be... brought in over 20% of the total amount pledged.

marijn19• 13 years ago

Interesting. Their 200 dollar tier is basically my 'all backers' tier (name in a readme file). But I can probably come up with something slightly more valuable to offer at ~250€.

As for CoffeeScript support -- the only major piece missing there is an error-tolerant CoffeeScript parser. Given that, one could simply run the CoffeeScript compiler over code, and analyze the output. There'd be some shuffling with source maps needed to translate source locations in the various representations of the code, but that's a solved problem. Well, and of course you might see some translation artifacts. The CS output code is semantically close to the input, but there are differences.

larve2• 13 years ago

a signed copy of your book? :}

antirez5• 13 years ago

"Tern is not currently open source. I'd like it to be, but I have to pay my bills. So I'm running a crowd-funder where interested parties can pledge money. If successful, Tern will be released under an MIT license."

Very odd model... take your code.

marijn19• 13 years ago

What do you mean?

antirez5• 13 years ago

I mean that from my point of view "gimme money if you want that open sourced" is very bad approach.

Either build your closed source business, or try to earn from an open source product to pay the bills.

1) What is the current state of the source code? It could be a mess.

2) The value of open source is mostly in continued developments, support, community, not just in releasing the code itself.

3) If you have this mindset, who guarantees me that tomorrow you'll write plugins that are closed and ask again for money to release?

kayoone3• 13 years ago

Your development of Redis is sponsored by VMWare afaik (which is awesome and so is redis), so whats wrong with crowd-sponsoring this guy ?

Sure it might be a trust issue, and it might be better to release the code first and then ask for money, but as it looks this guy has a good reputation in the community so i dont see too much of a problem.

antirez5• 13 years ago

I talk from a general point of view of my ideas, not as the Redis developer. Anyway for 1 year I worked at Redis for free, and it was open source since day 0.

hderms• 13 years ago

do you really think these two projects are comparable, or for that matter, that their code-licensing models are comparable?

EzGraphs• 13 years ago

IntelliJ's WebStorm has pretty JavaScript code completion and related tools. It also has plugins for popular libraries and frameworks, node.js and a variety of other HTML5 / latest-web-coolness stuff. Seems like a lot of folks in the AngularJS community have been using it it as well.

Disclaimer: I liked it enough to buy a personal license :), but am not affiliated with the folks who make and sell it.

ScottSauyet• 13 years ago

Just contributed, as I'm intrigued. Have you seen Chris Granger's LightTable? (http://www.lighttable.com/) I think there's some overlap, although his vision is much broader.

bsimpson3• 13 years ago

Chris commented above that Marijn is working on LightTable.

marijn19• 13 years ago

Not on LightTable itself, but on the editor component they use (http://codemirror.net)

serkanyersen• 13 years ago

Backed, I really love to see this working on SublimeText. I tired it with my own code and it managed to bring correct return types and object properties from all functions. I hope you release it soon. Thanks for the effort

talmand• 13 years ago

On my Mac (10.6.8), using Firefox 19.0 I get the right mouse contextual menu when I use CTRL-SPACE in the first example with the Tern selections displaying behind it. I don't see this behavior in Chrome or Safari.

gruseom2• 13 years ago

Marijn Haverbeke has a stellar track record of work in this area, so this should be taken more seriously than usual.

ibdknox• 13 years ago

Just to lend some more credence to this statement, we (LightTable) have actually contracted him to work on CodeMirror and have been nothing but happy with the results. He runs a tight ship and the output is great. CodeMirror is a fantastic editor (I say this as an ex PM on the Visual Studio editor) that continues to get better every day, it has been invaluable to our work.

shaunxcode• 13 years ago

To be clear the author of this IS the author of code mirror! That should be in large bold letters on that first page (it is on the crowd sourcing page). My first thought was "really? this is just code mirror with added cleverness, sort of lame to profit from it" - totally different story when it's the author adding value to something he has already contributed to the community. In that case this is the "premium" plan for code mirror.

marijn19• 13 years ago

Note that Tern's core is editor-independent. I made the demo on top of CodeMirror, obviously, since I know it very well. But the meat of this project does not have anything to with the editor that's used to interact with it.

robbrown4514• 13 years ago

Still, I wouldn't be shy about the fact that you did CodeMirror. It makes a huge difference to me....you are a known quantity and convinces me that this is a solid project.

And I'd think that CodeMirror is the obvious thing to hook this into, for the rest of us as well.

mishoo2• 13 years ago

That "added cleverness" is a big story in itself. Linking it with an editor is trivial. If you never tried to do static analysis on a dynamic language like JS you can't really appreciate just how smart Tern is (or wants to be).

slajax• 13 years ago

This is really great work. I'd love to see it for VIM.

MrUnderhill• 13 years ago

Looks like VIM is one of his first priorities. From the indiegogo page:

> The funding goal is computed to allow me to work for three months at about half the income I make with my usual consulting work. (The other half is made up in the satisfaction of building the thing I want to build.) In addition, I'll spend some of it to engage a Vim expert to help me build the Vim plug-in in a way that fits the culture for that editor.

Definitely chipping in.

bsimpson3• 13 years ago

Curious how this compares to Brackets. I haven't played with their latest sprint yet, but they also seem to be working on adding auto-complete to JS in CodeMirror.

Tern – Intelligent JavaScript editing

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