re.sub() replaces only several matches

[arysin]

BPO	12078
Nosy	@ezio-melotti
Superseder	bpo-11957: re.sub confusion between count and flags args
Files	repl.sh: sed replace which works repl.py: Python replace which does not work test.txt: Text to replace

^{Note: these values reflect the state of the issue at the time it was migrated and might not reflect the current state.}

Show more details

GitHub fields:

assignee = None
closed_at = <Date 2011-05-14.21:49:39.374>
created_at = <Date 2011-05-14.15:04:53.100>
labels = ['expert-regex']
title = 're.sub() replaces only several matches'
updated_at = <Date 2011-05-14.22:13:00.721>
user = 'https://bugs.python.org/arysin'

bugs.python.org fields:

activity = <Date 2011-05-14.22:13:00.721>
actor = 'arysin'
assignee = 'none'
closed = True
closed_date = <Date 2011-05-14.21:49:39.374>
closer = 'ezio.melotti'
components = ['Regular Expressions']
creation = <Date 2011-05-14.15:04:53.100>
creator = 'arysin'
dependencies = []
files = ['21999', '22000', '22001']
hgrepos = []
issue_num = 12078
keywords = []
message_count = 4.0
messages = ['135975', '135980', '135992', '135995']
nosy_count = 3.0
nosy_names = ['ezio.melotti', 'mrabarnett', 'arysin']
pr_nums = []
priority = 'normal'
resolution = 'duplicate'
stage = 'resolved'
status = 'closed'
superseder = '11957'
type = None
url = 'https://bugs.python.org/issue12078'
versions = ['Python 3.1']

[arysin]

When trying to replace strings with parenthesis (in the given example - alternative writing of the words in Ukrainian) the sed replace performs correctly replacing all occurrences, while python3 re.sub() function replaces only first two

[mrabarnett]

Argument 4 of re.sub is the maximum number of replacements, NOT flags:

Help on function sub in module re:

sub(pattern, repl, string, count=0, flags=0)
    Return the string obtained by replacing the leftmost
    non-overlapping occurrences of the pattern in string by the
    replacement repl.  repl can be either a string or a callable;
    if a string, backslash escapes in it are processed.  If it is
    a callable, it's passed the match object and must return
    a replacement string to be used.

re.I is 2, so you're telling it to perform at most 2 replacements.

[ezio-melotti]

See bpo-11957.

[arysin]

Ahh, I guess I should have read the docs. But then looks like I am not the fist or only one so it's not as embarrassing. :)

I would support the proposal in bpo-11957 to make re flags non-int object