Example.py

import re

fnames = ["r2.playlist.bbc.co.uk.js","bbc.co.uk.js"]
doms = ["www.bbc.co.uk","bbc.co.uk","bbcnco.uk","notthebbc.co.uk"]

for filename in fnames:
	print "-----\nFilename: "+filename+"\n-----"
	for domain in doms:
		print "Domain: "+domain
		
		# Trial A
		sre = re.compile('.*'+filename.split('.js')[0])
		if sre.match(domain):
			print "A: Yes!"
		else:
			print "A: No"
		
		# Trial B
		sre = re.compile('(.+\.)?'+re.escape(filename.split('.js')[0]))
		if sre.match(domain):
			print "B: Yes!"
		else:
			print "B: No"

The Output

-----
Filename: r2.playlist.bbc.co.uk.js
-----
Domain: www.bbc.co.uk
A: No
B: No
Domain: bbc.co.uk
A: No
B: No
Domain: bbcnco.uk
A: No
B: No
Domain: notthebbc.co.uk
A: No
B: No
-----
Filename: bbc.co.uk.js
-----
Domain: www.bbc.co.uk
A: Yes!
B: Yes!
Domain: bbc.co.uk
A: Yes!
B: Yes!
Domain: bbcnco.uk
A: Yes!
B: No
Domain: notthebbc.co.uk
A: Yes!
B: No