Python regex error: “cannot refer to an open 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
edited Nov 12 '18 at 7:28
Anthon
29.9k1693147
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick Thorpe
6411
|
show 3 more comments
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
edited Nov 12 '18 at 7:28
Anthon
29.9k1693147
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick Thorpe
6411
Can you try to print the regex? Also, try it without the( [Ss]* 1 )and see if it errors.
– sln
Nov 11 '18 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 '18 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 '18 at 19:29
Then, remove the end group and just put1at the end, as a test.
– sln
Nov 11 '18 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)Note that you have to escape the dash in the class if you want it to be literal-
– sln
Nov 11 '18 at 19:34
|
show 3 more comments
I am creating rules for a reddit automoderator. It gets its rules from a YAML config file and the regexes are interpreted as Python regex.
I am trying to make the following regular expression work:
(https?://[\w\d:#@%/;$()~_?+-=\.&]+\.\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
edited Nov 12 '18 at 7:28
Anthon
29.9k1693147
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick Thorpe
6411
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 '18 at 7:28
Anthon
29.9k1693147
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick Thorpe
6411
edited Nov 12 '18 at 7:28
Anthon
29.9k1693147
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick Thorpe
6411
edited Nov 12 '18 at 7:28
Anthon
29.9k1693147
edited Nov 12 '18 at 7:28
Anthon
29.9k1693147
edited Nov 12 '18 at 7:28
Anthon
29.9k1693147
29.9k1693147
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick Thorpe
6411
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick Thorpe
6411
asked Nov 11 '18 at 19:13
Patrick ThorpePatrick 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 '18 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 '18 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 '18 at 19:29
Then, remove the end group and just put1at the end, as a test.
– sln
Nov 11 '18 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1)Note that you have to escape the dash in the class if you want it to be literal-
– sln
Nov 11 '18 at 19:34
|
show 3 more comments
Can you try to print the regex? Also, try it without the( [Ss]* 1 )and see if it errors.
– sln
Nov 11 '18 at 19:23
I cannot print the regex, as I am just setting rules in YAML and they are being interpreted by someone else's python code. It does not have errors without the end group.
– Patrick Thorpe
Nov 11 '18 at 19:28
That error is thrown if you reference a group inside the group like this so it could be the closing)is not being seen.
– sln
Nov 11 '18 at 19:29
Then, remove the end group and just put1at the end, as a test.
– sln
Nov 11 '18 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test((https?://[wd:#@%/;$()~_?+-=.&]+.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 '18 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 '18 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 '18 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 '18 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 '18 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 '18 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 '18 at 19:29
Then, remove the end group and just put
1 at the end, as a test.– sln
Nov 11 '18 at 19:30
Then, remove the end group and just put
1 at the end, as a test.– sln
Nov 11 '18 at 19:30
And, it wouldn't hurt to escape the forward slashes for a test
((https?://[wd:#@%/;$()~_?+-=.&]+.w2,6)([Ss]*1) Note that you have to escape the dash in the class if you want it to be literal -– sln
Nov 11 '18 at 19:34
And, it wouldn't hurt to escape the forward slashes for a test
((https?://[wd:#@%/;$()~_?+-=.&]+.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 '18 at 19:34
|
show 3 more comments
1 Answer
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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 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
add a comment |
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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 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
add a comment |
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 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
add a comment |
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 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
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 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
answered Nov 11 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
answered Nov 11 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
answered Nov 11 '18 at 20:27
Patrick ThorpePatrick Thorpe
6411
6411
add a comment |
add a comment |
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Can you try to print the regex? Also, try it without the
( [Ss]* 1 )and see if it errors.– sln
Nov 11 '18 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 '18 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 '18 at 19:29
Then, remove the end group and just put
1at the end, as a test.– sln
Nov 11 '18 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 '18 at 19:34