how to find a function definition using AST

[Robert Brewer]

Stephen Emslie wrote:
> I am using the compiler.visitor module to examine a piece of code and
> extract certain useful information. However, I have run into 
> trouble that I
> dont know how to solve. When I override visitCallFunc I can 
> get the name of
> the function being called, but thats about it. What I would 
> really like is
> to know exactly where that function is defined (line of code, 
> what class if
> belongs to, everything).
> 
> I had a thought that when one prints the node argument from 
> visitCallFunc
> then you can see a node which looks something like 
> Getattr(Name('catfish'),
> 'double'. Perhaps if this statement could be evaluated then 
> the function in
> question could be found.
> 
> class MyVisitor(visitor.ASTVisitor):
>     def visitCallFunc(self,node):
>         print node

Hi Stephen,

You might notice (by looking at compiler.visitor source code) that, if
you define visitCallFunc, you have to continue walking that node on your
own--it isn't done for you. You might modify visitCallFunc to do the
same thing that the default() method does (after your print statement,
perhaps):

    def default(self, node, *args):
        for child in node.getChildNodes():
            self.dispatch(child, *args)

Also, note that a CallFunc Node obtains a set of attributes which other
Nodes don't have: