Not sure where a good place to start is. They're no different than ASTs for any other language. uglify-js dumps out a big nested array which is a pretty good start if you want to see about what is going on.
I got started in meta-programming with Bison which is a C parser and Flex which is a C scanner. (I mean, they don't parse and scan C, they are general purpose parsers which happen to be written in C). Basically you just take a source file and run it through a scanner which turns it into a bunch of "tokens" which are just one step up from raw source (parse something like "var hello = 1" into [t_VAR', 'hello', t_EQ, 1]), and then the parser takes those tokens and turns them into a meaningful tree. On Thu, Aug 30, 2012 at 2:23 PM, Dan Milon <danmi...@gmail.com> wrote: > Out of topic, but you gave me the clues. > Do you know where i can read up about AST trees for javascript? > > Thanks a ton, > danmilon. > > > On 08/30/2012 12:27 AM, Marcel Laverdet wrote: > >> Just curious why you need the comments in the AST at all? If you've got >> the start position & length of every token in the AST (much easier to do) >> you implicitly have the comments as well. The "fiber" engine in Streamline ( >> https://github.com/Sage/**streamlinejs/blob/master/lib/** >> fibers/transform.js<https://github.com/Sage/streamlinejs/blob/master/lib/fibers/transform.js>) >> does this with really good results. >> >> On Wed, Aug 29, 2012 at 8:37 AM, Mihai Călin Bazon >> <mihai.ba...@gmail.com<mailto: >> mihai.ba...@gmail.com>**> wrote: >> >> Well, the code generator doesn't yet have an option to keep comments, >> but I can add it easily; the harder part was having them in the AST, >> and that's done. >> >> What exactly are you trying to achieve? My understanding is that you >> compile Lisp to JS (cool!), do you want to be able to do the reverse >> transform? If so, perhaps a better idea is to generate a source map. >> (not sure what you need to do though, just guessing) >> >> Cheers, >> -Mihai >> >> On Wed, Aug 29, 2012 at 1:52 PM, Scott Taylor >> <sc...@railsnewbie.com <mailto:sc...@railsnewbie.com>**> wrote: >> > Wonderful! I've been working on a project that is sort of like >> parenscript >> > - but much more of a straight javascript in lisp/scheme clothes >> with a >> > define-syntax macro system. >> > >> > >> https://github.com/**smtlaissezfaire/loop<https://github.com/smtlaissezfaire/loop> >> > >> > I've been hacking on the 1x source of uglify to translate >> javascript into a >> > lispy type system (and back) - but inline comments have been a >> cause of >> > concern. Where is the 2.x source at this point? >> > >> > Cheers, >> > >> > Scott >> > >> > On Aug 28, 2012, at 12:56 PM, Mihai Călin Bazon wrote: >> > >> > On Tue, Aug 28, 2012 at 5:33 AM, Scott Taylor >> <sc...@railsnewbie.com <mailto:sc...@railsnewbie.com>**> wrote: >> > >> > Very cool. What comments in the AST are you going to preserve? >> > >> > >> > The new AST is able to store all comments, and the compressor >> and code >> > generator will be able to keep most of them. However, I suspect >> that >> > in general people will only need to store copyright notices, and >> those >> > usually start with some special marker like "/*!". It'll be easy to >> > add a configuration option to keep such comments, as long as they're >> > not in code that's going to be dropped (for example dead code, like, >> > code that follows a return, throw, break or continue statement). >> > >> > Cheers, >> > -- >> > Mihai Bazon, >> > http://mihai.bazon.net/blog >> > >> > -- >> > Job Board: http://jobs.nodejs.org/ >> > Posting guidelines: >> > https://github.com/joyent/**node/wiki/Mailing-List-** >> Posting-Guidelines<https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines> >> > You received this message because you are subscribed to the Google >> > Groups "nodejs" group. >> > To post to this group, send email to nodejs@googlegroups.com >> <mailto:nodejs@googlegroups.**com <nodejs@googlegroups.com>> >> >> > To unsubscribe from this group, send email to >> > >> nodejs+unsubscribe@**googlegroups.com<nodejs%2bunsubscr...@googlegroups.com> >> >> <mailto:nodejs%2Bunsubscribe@**googlegroups.com<nodejs%252bunsubscr...@googlegroups.com> >> > >> >> > For more options, visit this group at >> > >> http://groups.google.com/**group/nodejs?hl=en?hl=en<http://groups.google.com/group/nodejs?hl=en?hl=en> >> > >> > >> > -- >> > Job Board: http://jobs.nodejs.org/ >> > Posting guidelines: >> > https://github.com/joyent/**node/wiki/Mailing-List-** >> Posting-Guidelines<https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines> >> > You received this message because you are subscribed to the Google >> > Groups "nodejs" group. >> > To post to this group, send email to nodejs@googlegroups.com >> <mailto:nodejs@googlegroups.**com <nodejs@googlegroups.com>> >> >> > To unsubscribe from this group, send email to >> > >> nodejs+unsubscribe@**googlegroups.com<nodejs%2bunsubscr...@googlegroups.com> >> >> <mailto:nodejs%2Bunsubscribe@**googlegroups.com<nodejs%252bunsubscr...@googlegroups.com> >> > >> >> > For more options, visit this group at >> > >> http://groups.google.com/**group/nodejs?hl=en?hl=en<http://groups.google.com/group/nodejs?hl=en?hl=en> >> >> >> >> -- >> Mihai Bazon, >> http://mihai.bazon.net/blog >> >> -- >> Job Board: http://jobs.nodejs.org/ >> Posting guidelines: >> https://github.com/joyent/**node/wiki/Mailing-List-** >> Posting-Guidelines<https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines> >> You received this message because you are subscribed to the Google >> Groups "nodejs" group. >> To post to this group, send email to nodejs@googlegroups.com >> <mailto:nodejs@googlegroups.**com <nodejs@googlegroups.com>> >> >> To unsubscribe from this group, send email to >> >> nodejs+unsubscribe@**googlegroups.com<nodejs%2bunsubscr...@googlegroups.com> >> >> <mailto:nodejs%2Bunsubscribe@**googlegroups.com<nodejs%252bunsubscr...@googlegroups.com> >> > >> >> For more options, visit this group at >> >> http://groups.google.com/**group/nodejs?hl=en?hl=en<http://groups.google.com/group/nodejs?hl=en?hl=en> >> >> >> -- >> Job Board: http://jobs.nodejs.org/ >> Posting guidelines: https://github.com/joyent/**node/wiki/Mailing-List-** >> Posting-Guidelines<https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines> >> You received this message because you are subscribed to the Google >> Groups "nodejs" group. >> To post to this group, send email to nodejs@googlegroups.com >> To unsubscribe from this group, send email to >> nodejs+unsubscribe@**googlegroups.com<nodejs%2bunsubscr...@googlegroups.com> >> For more options, visit this group at >> http://groups.google.com/**group/nodejs?hl=en?hl=en<http://groups.google.com/group/nodejs?hl=en?hl=en> >> > > -- > Job Board: http://jobs.nodejs.org/ > Posting guidelines: https://github.com/joyent/**node/wiki/Mailing-List-** > Posting-Guidelines<https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines> > You received this message because you are subscribed to the Google > Groups "nodejs" group. > To post to this group, send email to nodejs@googlegroups.com > To unsubscribe from this group, send email to > nodejs+unsubscribe@**googlegroups.com<nodejs%2bunsubscr...@googlegroups.com> > For more options, visit this group at > http://groups.google.com/**group/nodejs?hl=en?hl=en<http://groups.google.com/group/nodejs?hl=en?hl=en> > -- Job Board: http://jobs.nodejs.org/ Posting guidelines: https://github.com/joyent/node/wiki/Mailing-List-Posting-Guidelines You received this message because you are subscribed to the Google Groups "nodejs" group. 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