A slightly faster way to decode ints and floats?

test_int_decode.py

import os
import random
import re
import time

l = []
for x in range(100000):
    l.append(random.choice(
        [None, str(random.randint(-10000, 10000)),
            str(random.random()),
        os.urandom(100)]))

INT_RE = re.compile(r'^[-+]?\d+$')
FLOAT_RE = re.compile(r'^[-+]?[0-9]*.[0-9]+(e[-+]\d+)?$')


def decode_re(messages):
    l = []
    for x in messages:
        if x is None:
            r = x
        elif INT_RE.match(x):
            r = int(x)
        elif FLOAT_RE.match(x):
            r = float(x)
        else:
            r = x
        l.append(r)
    return l


def decode_old(messages):
    l = []
    for x in messages:
        if x is None:
            r = x
        else:
            try:
                r = int(x) if x.find('.') == -1 else float(x)
            except ValueError:
                r = x
        l.append(r)
    return l


def main():
    re_time = 0
    int_time = 0
    N = 10
    for x in range(N):
        t = time.clock()
        l1 = decode_old(l)
        int_time += (time.clock() - t)
        t = time.clock()
        l2 = decode_re(l)
        re_time += (time.clock() - t)
        if l1 != l2:
            for a, b in zip(l1, l2):
                if a != b:
                    t = (a, type(a), b, type(b))
                    print '\"%s\" (%s)(old) != \"%s\" (%s)(re)' % t
            print 'Error: results don\'t match'
            break
    re_time /= N
    int_time /= N
    print 'old fn time: %f' % int_time
    print 'new fn time: %f' % re_time
    fn_name = 'old' if int_time < re_time else 'new'
    faster = 1.0 - (int_time / re_time if int_time < re_time
            else re_time / int_time)
    t = (fn_name, faster * 100, abs(re_time - int_time))
    print '%s is %f%% faster (%f seconds delta)' % t
    print 'average of %d iterations' % (N,)

if __name__ == '__main__':
    main()