From: Siddharth  Karandikar <siddharth.karandikar@...>
Date: 2006-12-13T20:15:09+09:00
Subject: Re: hpricot selective text modification

Thanks Peter.
I need to improve my knowledge abt DOM in general.

I have modified the code and do "if p.instance_of? Hpricot::Elem and
...."
Right now, Its working fine for me. Still need to think abt all the
possible cases.

Thanks,
Siddharth

On Dec 13, 3:55 pm, Peter Szinek <p...@rubyrailways.com> wrote:
> > Am I making any mistake?Sure :).
>
> Some W3C DOM theory:
>
> A document consists of different Nodes - in practice subclasses of Node:
> Element, Document, Attribute, Comment, Text, ProcessingInstruction etc
> (just from the top of my head - there are some more like
> DocumentFragment , CData, ... but it is unlikely you will need them
> here). Not every Node has a name, or children, or parent, or xxx. You
> have to make sure that the subclass of Node you are talking to is
> actually responding to a method you are trying to send him.
>
> a Hpricot DOM is not exactly a W3C DOM, but it is mostly similar:
>
> Only HPricot::Element has children, (not HPricot::Document or
> HPricot::Comment or...) and also not every Node has a name - like in
> your example HPricot::Document (Similarly HPricot::Text or
> HPricot::Comment does not have a name...). Also A HPricot::Document does
> not have a parent I think.
>
> Your problem is that you are traversing up, and reach the Document node
> which does not have a method name.
>
> So you have to modify your code like this:
>
> if text.parent and text.parent.name and text.parent.name != 'java' and
>
> to
>
> parent = text.parent
> if (parent.instance_of? Hpricot::Text) #or with respond_to, or with
> parent.parent == nil
>   #do the stuff
> else
>   #you have reached the top Node - Document; nothing to do
> end
>
> (The else branch is not needed, I just added it for illustration)
> 
> HTH,
> Peter
> 
> __http://www.rubyrailways.com