Question

I’m trying to add anchors to all h2’s in my html, using python. This code will add those anchors, but I need to fill the name of the anchors too.

Any idea if the name can be the number of the match in the loop or a slugified version of the text between the h2 tags?

Here’s the code so far:

regex = '(?P<name><h2>.*?</h2>)'
text = re.sub(regex, "<a name=''/>"+r"\g<name>", text)

Answer 1

You can take advantage of the fact that the second argument to re.sub can be a function to do pretty much anything you’d like. Here’s an example that will slugify the text inside the <h2> element:

regex = '(?P<name><h2>(.*?)</h2>)' # Note the extra group inside the <h2>

def slugify(s):
    return s.replace(' ', '-') # bare-bones slugify

def anchorize(matchobj):
    return '<a name="%s"/>%s' % (slugify(matchob.group(2)), matchobj.group(1))

text = re.sub(regex, anchorize, text)

(That slugify function could obviously use some work.)

You could also implement a counter with a version of anchorize that used a global counter or, better yet, a class that kept track of its own counter and implemented the special __call__ method.