Python's Regular Expression Source String Length

Question

In Python Regular Expressions,

re.compile(\"x\"*50000)

gives me OverflowError: regular expression code size limit exceeded

Answer 1

you want to match 50000 "x"s , correct??? if so, an alternative without regex

if "x"*50000 in mystring:
    print "found"

if you want to match 50000 "x"s using regex, you can use range

>>> pat=re.compile("x{50000}")
>>> pat.search(s)
<_sre.SRE_Match object at 0xb8057a30>

on my system it will take in length of 65535 max

>>> pat=re.compile("x{65536}")
Traceback (most recent call last):
  File "", line 1, in 
  File "/usr/lib/python2.6/re.py", line 188, in compile
    return _compile(pattern, flags)
  File "/usr/lib/python2.6/re.py", line 241, in _compile
    p = sre_compile.compile(pattern, flags)
  File "/usr/lib/python2.6/sre_compile.py", line 529, in compile
    groupindex, indexgroup
RuntimeError: invalid SRE code
>>> pat=re.compile("x{65535}")
>>>

I don't know if there are tweaks in Python we can use to increase that limit though.