Re: Perl Abstract/Concrete Syntax Tree
Andrew Potozniak wrote in perl.qa : > I was wondering if there was anything built in Perl (a Module) that > will take in a Perl file and parse that into an abstract or concrete syntax > tree. I searched around cpan for a bit and couldn't find what I was looking > for. If anyone is wondering what I'm talking about there is a nice Java > package that Eclipse uses to create a tree for Java compilation that I can > point you toward. Thanks for your time. Hm -- as the task of parsing perl involves some complex interplay between compile-time and run-time -- think about the function prototypes, for example -- perl can't be described by a non-ambiguous grammar, and can't be parsed accurately by tools that don't include a full-fledged perl interpreter already. However, during parsing, perl builds internally an abstract syntax tree for its own usage ; the syntax tree is then walked during execution. It's possible to stop the perl interpreter after the compilation of the main program and to have it print the current contents of the parse tree. This is achieved by the O and B::* modules, that come with perl. You may want something not too far from this : $ perl -MO=Concise -e 'print $a + $b' 8 <@> leave[1 ref] vKP/REFC ->(end) 1 <0> enter ->2 2 <;> nextstate(main 1 -e:1) v ->3 7 <@> print vK ->8 3<0> pushmark s ->4 6<2> add[t1] sK/2 ->7 - <1> ex-rv2sv sK/1 ->5 4 <$> gvsv(*a) s ->5 - <1> ex-rv2sv sK/1 ->6 5 <$> gvsv(*b) s ->6 -e syntax OK See the docs for O, B and B::Concise for more information.
Re: Perl Abstract/Concrete Syntax Tree
--- "Potozniak, Andrew" <[EMAIL PROTECTED]> wrote: > Hi, > > I was wondering if there was anything built in Perl (a Module) that > will take in a Perl file and parse that into an abstract or concrete > syntax > tree. I searched around cpan for a bit and couldn't find what I was > looking > for. If anyone is wondering what I'm talking about there is a nice > Java > package that Eclipse uses to create a tree for Java compilation that > I can > point you toward. Thanks for your time. > > ~~Andrew Andrew, I'm a bit confused. Eclipse is simply an IDE, so that doesn't help me understand what you're looking for. As for turning a file into a "syntax tree", what do you mean? Files are in many different formats. I can't imagine a single module handling CSV, XML, and binary JPEG files the same way. If you could be a bit more concrete in what you are looking for, we would be better prepared to help. Perhaps if you could send a code snippet of what you would *like* Perl to do (and specify the file format(s) that you want to work with). Cheers, Ovid = Silence is Evilhttp://users.easystreet.com/ovid/philosophy/indexdecency.htm Ovid http://www.perlmonks.org/index.pl?node_id=17000 Web Programming with Perl http://users.easystreet.com/ovid/cgi_course/
Perl Abstract/Concrete Syntax Tree
Hi, I was wondering if there was anything built in Perl (a Module) that will take in a Perl file and parse that into an abstract or concrete syntax tree. I searched around cpan for a bit and couldn't find what I was looking for. If anyone is wondering what I'm talking about there is a nice Java package that Eclipse uses to create a tree for Java compilation that I can point you toward. Thanks for your time. ~~Andrew
