Comments on: Parsing Javascript Parser

By: Ruby Tutorial: Scraping Muxtape for mp3 + iTunes playlist creation « Leveraging Visionary Paradigms

Sun, 20 Apr 2008 23:50:21 +0000

[...] since the JavaScript to parse is not all that hard. To do the parsing, I briefly considered RKelly, which looks very interesting, but there is no gem yet, so I passed. I just use Hpricot to parse [...]

By: Aaron Patterson

Aaron Patterson — Thu, 03 Jan 2008 23:30:05 +0000

Thanks! Absolutely. All nodes in the parse tree implement the to_dots method. So if you find your node, you can call .to_dots on it and get the parse tree below it.

Here is the code:

parser = RKelly::Parser.new

tree = parser.parse(File.read(ARGV[0]))

puts tree.value.find { |x| x.value == ‘$’ }.to_dots

Here is the dot file. Here is the image:

By: Andrew Dupont

Andrew Dupont — Thu, 03 Jan 2008 22:40:31 +0000

Great work, Aaron. Think you could generate a chart of some small portion of Prototype, like the $ function?

We've been looking at rbNarcissus as a possible foundation for some internal tools that would make the Prototype Core team's lives easier, but it looks like RKelly might be the better way to go.

By: Aaron Patterson

Aaron Patterson — Wed, 26 Dec 2007 21:26:16 +0000

Not yet. The parse tree is not quite the same. I may get it to output the same thing as ParseTree, but for now I’m focusing on writing an interpreter.

By: Chris Anderson

Chris Anderson — Wed, 26 Dec 2007 21:14:37 +0000

Does RKelly output the same as ParseTree? Maybe you could teach it to, and then execute the Javascript as Ruby. How wicked is that?