Python regex error: “cannot refer to an open group”
up vote
-1
down vote
favorite
I am creating rules for a reddit automoderator. It gets its rules from a YAML config file and the regexes are interpreted as Python regex.
I am trying to make the following regular expression work:
(https?://[\w\d:#@%/;$()~_?+-=\.&]+\.\w2,6)([\S\s]*\1)
When I test it on https://pythex.org/ it works perfectly to achieve what I want.
Unfortunately my group reference at the end of the expression is causing an error when I copy the same regex into the config file:
Generated an invalid regex for
body (regex)
: cannot refer to an open
group
I have also tried this version with everything escaped just to make sure that the characters weren't interfering in any way:
(https?://[\w\d\:\#\@\%\/\;\$\(\)\~\_\?\+\-\=\.&]+\.\w2,6)([\S\s]*\1)
But I still get the same error. Does anyone know what I'm doing wrong here?
regex regex-group
|
show 3 more comments
up vote
-1
down vote
favorite
I am creating rules for a reddit automoderator. It gets its rules from a YAML config file and the regexes are interpreted as Python regex.
I am trying to make the following regular expression work:
(https?://[\w\d:#@%/;$()~_?+-=\.&]+\.\w2,6)([\S\s]*\1)
When I test it on https://pythex.org/ it works perfectly to achieve what I want.
Unfortunately my group reference at the end of the expression is causing an error when I copy the same regex into the config file:
Generated an invalid regex for
body (regex)
: cannot refer to an open
group
I have also tried this version with everything escaped just to make sure that the characters weren't interfering in any way:
(https?://[\w\d\:\#\@\%\/\;\$\(\)\~\_\?\+\-\=\.&]+\.\w2,6)([\S\s]*\1)
But I still get the same error. Does anyone know what I'm doing wrong here?
regex regex-group
Can you try to print the regex? Also, try it without the( [Ss]* 1 )
and see if it errors.
– sln
Nov 11 at 19:23
I cannot print the regex, as I am just setting rules in YAML and they are being interpreted by someone else's python code. It does not have errors without the end group.
– Patrick Thorpe
Nov 11 at 19:28
That error is thrown if you reference a group inside the group like this so it could be the closing)
is not being seen.
– sln
Nov 11 at 19:29
Then, remove the end group and just put1
at the end, as a test.
– sln
Nov 11 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)
Note that you have to escape the dash in the class if you want it to be literal-
– sln
Nov 11 at 19:34
|
show 3 more comments
up vote
-1
down vote
favorite
up vote
-1
down vote
favorite
I am creating rules for a reddit automoderator. It gets its rules from a YAML config file and the regexes are interpreted as Python regex.
I am trying to make the following regular expression work:
(https?://[\w\d:#@%/;$()~_?+-=\.&]+\.\w2,6)([\S\s]*\1)
When I test it on https://pythex.org/ it works perfectly to achieve what I want.
Unfortunately my group reference at the end of the expression is causing an error when I copy the same regex into the config file:
Generated an invalid regex for
body (regex)
: cannot refer to an open
group
I have also tried this version with everything escaped just to make sure that the characters weren't interfering in any way:
(https?://[\w\d\:\#\@\%\/\;\$\(\)\~\_\?\+\-\=\.&]+\.\w2,6)([\S\s]*\1)
But I still get the same error. Does anyone know what I'm doing wrong here?
regex regex-group
I am creating rules for a reddit automoderator. It gets its rules from a YAML config file and the regexes are interpreted as Python regex.
I am trying to make the following regular expression work:
(https?://[\w\d:#@%/;$()~_?+-=\.&]+\.\w2,6)([\S\s]*\1)
When I test it on https://pythex.org/ it works perfectly to achieve what I want.
Unfortunately my group reference at the end of the expression is causing an error when I copy the same regex into the config file:
Generated an invalid regex for
body (regex)
: cannot refer to an open
group
I have also tried this version with everything escaped just to make sure that the characters weren't interfering in any way:
(https?://[\w\d\:\#\@\%\/\;\$\(\)\~\_\?\+\-\=\.&]+\.\w2,6)([\S\s]*\1)
But I still get the same error. Does anyone know what I'm doing wrong here?
regex regex-group
regex regex-group
edited Nov 12 at 7:28
Anthon
28.2k1693144
28.2k1693144
asked Nov 11 at 19:13
Patrick Thorpe
6411
6411
Can you try to print the regex? Also, try it without the( [Ss]* 1 )
and see if it errors.
– sln
Nov 11 at 19:23
I cannot print the regex, as I am just setting rules in YAML and they are being interpreted by someone else's python code. It does not have errors without the end group.
– Patrick Thorpe
Nov 11 at 19:28
That error is thrown if you reference a group inside the group like this so it could be the closing)
is not being seen.
– sln
Nov 11 at 19:29
Then, remove the end group and just put1
at the end, as a test.
– sln
Nov 11 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)
Note that you have to escape the dash in the class if you want it to be literal-
– sln
Nov 11 at 19:34
|
show 3 more comments
Can you try to print the regex? Also, try it without the( [Ss]* 1 )
and see if it errors.
– sln
Nov 11 at 19:23
I cannot print the regex, as I am just setting rules in YAML and they are being interpreted by someone else's python code. It does not have errors without the end group.
– Patrick Thorpe
Nov 11 at 19:28
That error is thrown if you reference a group inside the group like this so it could be the closing)
is not being seen.
– sln
Nov 11 at 19:29
Then, remove the end group and just put1
at the end, as a test.
– sln
Nov 11 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)
Note that you have to escape the dash in the class if you want it to be literal-
– sln
Nov 11 at 19:34
Can you try to print the regex? Also, try it without the
( [Ss]* 1 )
and see if it errors.– sln
Nov 11 at 19:23
Can you try to print the regex? Also, try it without the
( [Ss]* 1 )
and see if it errors.– sln
Nov 11 at 19:23
I cannot print the regex, as I am just setting rules in YAML and they are being interpreted by someone else's python code. It does not have errors without the end group.
– Patrick Thorpe
Nov 11 at 19:28
I cannot print the regex, as I am just setting rules in YAML and they are being interpreted by someone else's python code. It does not have errors without the end group.
– Patrick Thorpe
Nov 11 at 19:28
That error is thrown if you reference a group inside the group like this so it could be the closing
)
is not being seen.– sln
Nov 11 at 19:29
That error is thrown if you reference a group inside the group like this so it could be the closing
)
is not being seen.– sln
Nov 11 at 19:29
Then, remove the end group and just put
1
at the end, as a test.– sln
Nov 11 at 19:30
Then, remove the end group and just put
1
at the end, as a test.– sln
Nov 11 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test
((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)
Note that you have to escape the dash in the class if you want it to be literal -
– sln
Nov 11 at 19:34
And, it wouldn't hurt to escape the forward slashes for a test
((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)
Note that you have to escape the dash in the class if you want it to be literal -
– sln
Nov 11 at 19:34
|
show 3 more comments
1 Answer
1
active
oldest
votes
up vote
0
down vote
accepted
I managed to fix the problem by changing the group selection to 2
instead of 1
.
It turned out that YAML or AutoModerator were automatically putting parentheses around the whole expression, so any group references within must be 1 more than you would initially expect.
I had thought that this was the problem at the start, and tried the fix explained above, however due to a separate issue with the AutoModerator code, the fix had not appeared to have worked. All resolved now though; thanks for your patience and help.
add a comment |
Your Answer
StackExchange.ifUsing("editor", function ()
StackExchange.using("externalEditor", function ()
StackExchange.using("snippets", function ()
StackExchange.snippets.init();
);
);
, "code-snippets");
StackExchange.ready(function()
var channelOptions =
tags: "".split(" "),
id: "1"
;
initTagRenderer("".split(" "), "".split(" "), channelOptions);
StackExchange.using("externalEditor", function()
// Have to fire editor after snippets, if snippets enabled
if (StackExchange.settings.snippets.snippetsEnabled)
StackExchange.using("snippets", function()
createEditor();
);
else
createEditor();
);
function createEditor()
StackExchange.prepareEditor(
heartbeatType: 'answer',
convertImagesToLinks: true,
noModals: true,
showLowRepImageUploadWarning: true,
reputationToPostImages: 10,
bindNavPrevention: true,
postfix: "",
imageUploader:
brandingHtml: "Powered by u003ca class="icon-imgur-white" href="https://imgur.com/"u003eu003c/au003e",
contentPolicyHtml: "User contributions licensed under u003ca href="https://creativecommons.org/licenses/by-sa/3.0/"u003ecc by-sa 3.0 with attribution requiredu003c/au003e u003ca href="https://stackoverflow.com/legal/content-policy"u003e(content policy)u003c/au003e",
allowUrls: true
,
onDemand: true,
discardSelector: ".discard-answer"
,immediatelyShowMarkdownHelp:true
);
);
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53252249%2fpython-regex-error-cannot-refer-to-an-open-group%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
1 Answer
1
active
oldest
votes
1 Answer
1
active
oldest
votes
active
oldest
votes
active
oldest
votes
up vote
0
down vote
accepted
I managed to fix the problem by changing the group selection to 2
instead of 1
.
It turned out that YAML or AutoModerator were automatically putting parentheses around the whole expression, so any group references within must be 1 more than you would initially expect.
I had thought that this was the problem at the start, and tried the fix explained above, however due to a separate issue with the AutoModerator code, the fix had not appeared to have worked. All resolved now though; thanks for your patience and help.
add a comment |
up vote
0
down vote
accepted
I managed to fix the problem by changing the group selection to 2
instead of 1
.
It turned out that YAML or AutoModerator were automatically putting parentheses around the whole expression, so any group references within must be 1 more than you would initially expect.
I had thought that this was the problem at the start, and tried the fix explained above, however due to a separate issue with the AutoModerator code, the fix had not appeared to have worked. All resolved now though; thanks for your patience and help.
add a comment |
up vote
0
down vote
accepted
up vote
0
down vote
accepted
I managed to fix the problem by changing the group selection to 2
instead of 1
.
It turned out that YAML or AutoModerator were automatically putting parentheses around the whole expression, so any group references within must be 1 more than you would initially expect.
I had thought that this was the problem at the start, and tried the fix explained above, however due to a separate issue with the AutoModerator code, the fix had not appeared to have worked. All resolved now though; thanks for your patience and help.
I managed to fix the problem by changing the group selection to 2
instead of 1
.
It turned out that YAML or AutoModerator were automatically putting parentheses around the whole expression, so any group references within must be 1 more than you would initially expect.
I had thought that this was the problem at the start, and tried the fix explained above, however due to a separate issue with the AutoModerator code, the fix had not appeared to have worked. All resolved now though; thanks for your patience and help.
answered Nov 11 at 20:27
Patrick Thorpe
6411
6411
add a comment |
add a comment |
Thanks for contributing an answer to Stack Overflow!
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Some of your past answers have not been well-received, and you're in danger of being blocked from answering.
Please pay close attention to the following guidance:
- Please be sure to answer the question. Provide details and share your research!
But avoid …
- Asking for help, clarification, or responding to other answers.
- Making statements based on opinion; back them up with references or personal experience.
To learn more, see our tips on writing great answers.
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
StackExchange.ready(
function ()
StackExchange.openid.initPostLogin('.new-post-login', 'https%3a%2f%2fstackoverflow.com%2fquestions%2f53252249%2fpython-regex-error-cannot-refer-to-an-open-group%23new-answer', 'question_page');
);
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Sign up or log in
StackExchange.ready(function ()
StackExchange.helpers.onClickDraftSave('#login-link');
);
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Sign up using Google
Sign up using Facebook
Sign up using Email and Password
Post as a guest
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Required, but never shown
Can you try to print the regex? Also, try it without the
( [Ss]* 1 )
and see if it errors.– sln
Nov 11 at 19:23
I cannot print the regex, as I am just setting rules in YAML and they are being interpreted by someone else's python code. It does not have errors without the end group.
– Patrick Thorpe
Nov 11 at 19:28
That error is thrown if you reference a group inside the group like this so it could be the closing
)
is not being seen.– sln
Nov 11 at 19:29
Then, remove the end group and just put
1
at the end, as a test.– sln
Nov 11 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test
((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)
Note that you have to escape the dash in the class if you want it to be literal-
– sln
Nov 11 at 19:34