Optimize re.search() for \A (and maybe ^) #87051

assignee = None
closed_at = <Date 2022-03-22.15:28:31.421>
created_at = <Date 2021-01-10.21:58:21.401>
labels = ['expert-regex', '3.10', 'performance']
title = 'Optimize re.search() for \\A (and maybe ^)'
updated_at = <Date 2022-03-22.15:28:31.421>
user = 'https://github.com/2d4d'

activity = <Date 2022-03-22.15:28:31.421>
actor = 'serhiy.storchaka'
assignee = 'none'
closed = True
closed_date = <Date 2022-03-22.15:28:31.421>
closer = 'serhiy.storchaka'
components = ['Regular Expressions']
creation = <Date 2021-01-10.21:58:21.401>
creator = '2d4d'
dependencies = []
files = ['49733']
hgrepos = []
issue_num = 42885
keywords = ['patch']
message_count = 6.0
messages = ['384782', '384805', '385137', '385138', '385142', '415789']
nosy_count = 5.0
nosy_names = ['ezio.melotti', 'mrabarnett', 'steven.daprano', 'serhiy.storchaka', '2d4d']
pr_nums = ['32021']
priority = 'normal'
resolution = 'fixed'
stage = 'resolved'
status = 'closed'
superseder = None
type = 'performance'
url = 'https://bugs.python.org/issue42885'
versions = ['Python 3.10']