It’s not every day that someone tries to add a new programming language to the web. There’s a good reason for that. The great trinity of web development — HTML, CSS and JavaScript — while not perfect, has proved itself highly flexible and capable of adapting as it evolves, which, in the end, might be more important than perfection.
But, regardless of how well those three have served the web thus far, they are not enough for Google, which is hoping the web will now embrace Dart, Google’s brand-new programming language for “structured web programming.”
The first hint of Dart surfaced about a month ago when an internal Google memo was leaked onto the web (the memo itself dates from 2010). In it Google claims that “JavaScript has fundamental flaws that cannot be fixed merely by evolving the language.” The answer, for Google, was to go off and create its own homebrewed solution.
That solution is Dart, a “class-based optionally typed programming language for building web applications.”
Lars Bak, a software engineer working on Dart, says the language is designed to work with every thing from “a one-person project without much structure to a large-scale project needing formal types in the code to state programmer intent.”
In other words, Dart is aiming to be a one-size-fits-all solution for writing apps on the web. Dart has been built from the ground up with this goal in mind. Indeed Dart offers some interesting tools, including optional types and the ability to declare private methods via an underscore. Unfortunately for Dart, a couple of novelties don’t seem to be winning over programmers. The Hacker News discussion thread on Dart is full of rather barbed critiques with hardly a supportive voice to be heard.
Dart on the web
Appealing to programmers is only half of what Dart needs to succeed; it also has to work well on the open web. For that Google has two solutions.
The first and ideal solution will be to execute Dart code in a browser-native virtual machine (very similar to how JavaScript is handled today). Of course that means the rest of the browser makers need to join Google in supporting Dart. Because that isn’t likely to happen any time soon, nor will it ever happen for legacy web browsers, Google has a fallback plan — a compiler that translates Dart code to JavaScript.
While the JavaScript compiler solution will mean slower web apps, it also means that Dart apps would always be able to run, regardless of the browser in question. That’s good for older browsers, but it also raises some questions about where Google plans to go with Dart.
Essentially, Google has set up a two-tier system for running Dart in the browser, and that is where Dart might run afoul of the open web.
Prior Dart Art
How Standards Proliferate by XKCD
The leaked Google memo that appeared on the web last month created a tempest in the web standards community teacup. The idea that Google had a secret project designed “to replace JavaScript as the lingua franca of web development” did not sit well with those who support open web standards.
The company appears to have backed off that stance somewhat for the official release. In fact, Google hardly mentions JavaScript in its Dart announcement and Lars Bak tells CNet that Dart is “not going to replace JavaScript…. JavaScript is a cornerstone of the web today, and it will continue to be for a long, long time.”
That message may be too little, too late. Publicly, Google may now be pushing the message that Dart is complimentary to JavaScript, but the blunter language and goals outlined in the leaked memo are already out there, fresh in developers’ minds. That, combined with Google’s less than stellar track record with its “open” projects may make it difficult for Dart to find supporters.
While Dart is open source and available for anyone to use, Google does not have a strong record of fostering open projects; that is, projects where the community can not just download and compile code (Andy Rubin’s “definition of open“) but can actually have a hand in creating features and guiding the direction of the project.
Until the latter component is well established, don’t expect other browser makers to adopt Dart. So long as Google controls the strings it’s unlikely its arch rivals like Microsoft and Apple will support Dart.
Without that support, Dart won’t be running in a virtual machine; instead it will fall back to running as JavaScript. That effectively means that, while Dart will run in any browser, it will likely have subpar performance in any browser lacking the virtual machine.
What standards proponents fear is a web where only Google’s Chrome browser ever fully supports Dart. That would mean that, while Dart apps would work everywhere, they’d be significantly faster in Chrome. That would send the web back to the bad old days of “works best in Internet Explorer” websites, only this time around it would be “works best in Google Chrome.”
Future Dart
It’s possible that Google will use Dart to finally create a true community-driven project. The company has already said it plans to eventually submit Dart for standardization, which would certainly help.
It’s too early to write off Dart, but it’s also too early to say it will be anything more than a novelty Google uses in its own apps (like WebP or even SPDY). Even if Dart can convince both developers and browser makers to jump on board, don’t look for Dart to become the “lingua franca of web development” any time soon.
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