[twill] Extending Twill Question

[Titus Brown]

On Fri, May 26, 2006 at 04:01:38PM -0700, Austin wrote:
-> Hi,
-> 
-> I'm pretty new to twill and python in general (installing both just 
-> yesterday :)) and was looking to see how I might add a couple new 
-> functions for personal use or if anyone was interested (I am not very 
-> clear on how the licensing works.) but need a bit of help getting started.

twill is completely open source and redistributable etc, unless you're
looking to sell it.  Then we should talk, or you should have a lawyer
check out the license.

Adding functions is pretty simple, as long as you don't need to modify
the core browser functionality; check out the extensions documentation at

http://issola.caltech.edu/~t/twill/doc/extensions.html

-> The first function is just forward, it looks like beyond adding 
-> functions in commands.py and browser.py, the real changes would have to 
-> be made in _mechanize.py since the History class doesn't seem to have 
-> any support for going forward. It also doesn't seem to know what the 
-> current page is which makes things a bit more difficult. I think I need 
-> to store the current page in the History class, and then make some kind 
-> of modifications in _mech_open, and to the functions defined in the 
-> history class. Is this the right direction for doing this, or am I 
-> missing something else?

Well, what's your goal with this?  Right now the history works like 
a simple stack; it wouldn't be hard to change it to be a list, if
that's what you need.  You're right that it doesn't get the current
page, but twill has that information... so it really depends on what
you want to do.

-> Second, I would like to be able to follow a link by its number printed 
-> out after using showlinks.
-> 
-> I added to commands.py:
-> 
-> def followbynum(num):
->      """
->      >> follow <link#>
-> 
->      Visit the page at position link# in the list returned by showlinks.
->      """
-> 
-> def follow_link_num(self, linknum):
->          """
->          Follow the link by its number on the page.
->          """

-> This seems to work right now, but I'm afraid there's something I am 
-> missing, or some error case that I'm not considering.

Nope, it looks good to me!

I could add this functionality in to 'follow' 'as is', actually, by just
choosing the link by number in 'follow' if it's an integer.  Any
objections, anyone?

cheers,
--titus