A faster version of the find_prefix_at_end() function (that I found in the

last Medusa release)

Should be safe as a bugfix candidate, though it's not fixing a bug.
This commit is contained in:
Andrew M. Kuchling 2002-03-20 02:22:58 +00:00
parent 913b9078cf
commit c63a396c5f
1 changed files with 7 additions and 9 deletions

View File

@ -280,20 +280,18 @@ def pop (self):
# characters matched.
# for example:
# f_p_a_e ("qwerty\r", "\r\n") => 1
# f_p_a_e ("qwerty\r\n", "\r\n") => 2
# f_p_a_e ("qwertydkjf", "\r\n") => 0
# f_p_a_e ("qwerty\r\n", "\r\n") => <undefined>
# this could maybe be made faster with a computed regex?
# [answer: no; circa Python-2.0, Jan 2001]
# python: 18307/s
# new python: 28961/s
# old python: 18307/s
# re: 12820/s
# regex: 14035/s
def find_prefix_at_end (haystack, needle):
nl = len(needle)
result = 0
for i in range (1,nl):
if haystack[-(nl-i):] == needle[:(nl-i)]:
result = nl-i
break
return result
l = len(needle) - 1
while l and not haystack.endswith(needle[:l]):
l -= 1
return l