Hello all,

I wrote the code below. It is simply a dictionary that uses regular
expressions to match keys. A quick look at _test() will give you an
example.

Is there a module that already does this? Is there a way and would it
be better to use list comprehension? (using python 2.3)

Just looking for a better or more pythonic way to do it.

import re

class ReDict(dict):
'''
A dictionary that uses regular expressions keys

NOTE:
if the redict finds more than one key that matches the re it
returns a redict of all of the matching keys
'''
def __init__(self):
dict.__init__(self)
self.re=1

def reOn(self):
'''
turn regular expression matching on
'''
self.re=1

def reOff(self):
'''
turn regular expression matching off
'''
self.re=0

def __getitem__(self,key):
if self.re ==1:
temp = ReDict()
for item in self.items():
if re.search(key,item[0]): #line match
temp[item[0]]=item[1]

if len(temp)==1:
return temp.values()[0]

return temp
else:
return dict.__getitem__(self,key)


def _test():
d=ReDict()

d["price"]=7.25
d['call jan 5.0']=1
d['call jan 7.5']=1.5
d['put jan 7.5']=7.2

d['call feb 5.0']=2
d['call feb 7.5']=2.5
d['put feb 7.5']=6.8

d['call mar 5.0']=3
d['call mar 7.5']=3.5
d['put mar 7.5']=4

d['call apr 5.0']=4
d['call apr 7.5']=4.5
d['put apr 7.5']=6.2

d['call may 5.0']=5
d['call may 7.5']=5.5
d['put may 7.5']=4.9

print d['price'] #prints the price
print d['call']['may']['7.5'] # prints individual value
print d['call'] #returns a redict of all calls
print d['put'] #returns a redict of all puts
print d['may'] #returns a redict of all options in may

_test()


Thanks,
Erik Lechak
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