How to to transform x^(…) to x^{…} even when brackets are inside? Pure Regex possible?
I need to change many posts and edit the content so that ^(...) becomes x^{...}.
What I have so far:
$regexpattern = "/^((.*?))/";
$replaceregex = "^{$1}";
$content_new = preg_replace($regexpattern, $replaceregex, $content);
which works.
However, I realized that if there is a round bracket inside the round wrapping brackets, it fails.
Example:
this should be transformed a^(x²) and this b^(-(x²))
becomes:
this should be transformed a^{x²} and this b^{-(x²})
Needed:
this should be transformed a^(x²) and this b^{-(x²)}
How can I prevent this and only replace the last bracket? Or do we need to use PHP and explode the content with ^(...) into Arrays and replace?
It could also be that there are multiple brackets inside (even if rare).
PS: After writing this question I found: https://stackoverflow.com/a/27052437/1066234 but there is no solution provided for this specific case.
php regex
edited Nov 12 '18 at 8:28
anubhava
520k46316390
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
add a comment |
I need to change many posts and edit the content so that ^(...) becomes x^{...}.
What I have so far:
$regexpattern = "/^((.*?))/";
$replaceregex = "^{$1}";
$content_new = preg_replace($regexpattern, $replaceregex, $content);
which works.
However, I realized that if there is a round bracket inside the round wrapping brackets, it fails.
Example:
this should be transformed a^(x²) and this b^(-(x²))
becomes:
this should be transformed a^{x²} and this b^{-(x²})
Needed:
this should be transformed a^(x²) and this b^{-(x²)}
How can I prevent this and only replace the last bracket? Or do we need to use PHP and explode the content with ^(...) into Arrays and replace?
It could also be that there are multiple brackets inside (even if rare).
PS: After writing this question I found: https://stackoverflow.com/a/27052437/1066234 but there is no solution provided for this specific case.
php regex
edited Nov 12 '18 at 8:28
anubhava
520k46316390
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
Regular expressions typically have problems with all kinds of nested structures.
– Some programmer dude
Nov 12 '18 at 8:15
What is expected output forthis should be transformed a^(x²) and this b^(-(x²))?
– anubhava
Nov 12 '18 at 8:22
1
this recursive expression regex101.com/r/Hlt37z/2 seems to work don't know if recursive expression are supported by preg_replace
– Nahuel Fouilleul
Nov 12 '18 at 8:25
add a comment |
I need to change many posts and edit the content so that ^(...) becomes x^{...}.
What I have so far:
$regexpattern = "/^((.*?))/";
$replaceregex = "^{$1}";
$content_new = preg_replace($regexpattern, $replaceregex, $content);
which works.
However, I realized that if there is a round bracket inside the round wrapping brackets, it fails.
Example:
this should be transformed a^(x²) and this b^(-(x²))
becomes:
this should be transformed a^{x²} and this b^{-(x²})
Needed:
this should be transformed a^(x²) and this b^{-(x²)}
How can I prevent this and only replace the last bracket? Or do we need to use PHP and explode the content with ^(...) into Arrays and replace?
It could also be that there are multiple brackets inside (even if rare).
PS: After writing this question I found: https://stackoverflow.com/a/27052437/1066234 but there is no solution provided for this specific case.
php regex
edited Nov 12 '18 at 8:28
anubhava
520k46316390
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
I need to change many posts and edit the content so that ^(...) becomes x^{...}.
What I have so far:
$regexpattern = "/^((.*?))/";
$replaceregex = "^{$1}";
$content_new = preg_replace($regexpattern, $replaceregex, $content);
which works.
However, I realized that if there is a round bracket inside the round wrapping brackets, it fails.
Example:
this should be transformed a^(x²) and this b^(-(x²))
becomes:
this should be transformed a^{x²} and this b^{-(x²})
Needed:
this should be transformed a^(x²) and this b^{-(x²)}
How can I prevent this and only replace the last bracket? Or do we need to use PHP and explode the content with ^(...) into Arrays and replace?
It could also be that there are multiple brackets inside (even if rare).
PS: After writing this question I found: https://stackoverflow.com/a/27052437/1066234 but there is no solution provided for this specific case.
php regex
php regex
edited Nov 12 '18 at 8:28
anubhava
520k46316390
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
edited Nov 12 '18 at 8:28
anubhava
520k46316390
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
edited Nov 12 '18 at 8:28
anubhava
520k46316390
edited Nov 12 '18 at 8:28
anubhava
520k46316390
edited Nov 12 '18 at 8:28
anubhava
520k46316390
520k46316390
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
asked Nov 12 '18 at 8:12
Kai Noack
6,189659115
6,189659115
Regular expressions typically have problems with all kinds of nested structures.
– Some programmer dude
Nov 12 '18 at 8:15
What is expected output forthis should be transformed a^(x²) and this b^(-(x²))?
– anubhava
Nov 12 '18 at 8:22
1
this recursive expression regex101.com/r/Hlt37z/2 seems to work don't know if recursive expression are supported by preg_replace
– Nahuel Fouilleul
Nov 12 '18 at 8:25
add a comment |
Regular expressions typically have problems with all kinds of nested structures.
– Some programmer dude
Nov 12 '18 at 8:15
What is expected output forthis should be transformed a^(x²) and this b^(-(x²))?
– anubhava
Nov 12 '18 at 8:22
1
this recursive expression regex101.com/r/Hlt37z/2 seems to work don't know if recursive expression are supported by preg_replace
– Nahuel Fouilleul
Nov 12 '18 at 8:25
Regular expressions typically have problems with all kinds of nested structures.
– Some programmer dude
Nov 12 '18 at 8:15
Regular expressions typically have problems with all kinds of nested structures.
– Some programmer dude
Nov 12 '18 at 8:15
What is expected output for
this should be transformed a^(x²) and this b^(-(x²))?– anubhava
Nov 12 '18 at 8:22
What is expected output for
this should be transformed a^(x²) and this b^(-(x²))?– anubhava
Nov 12 '18 at 8:22
1
1
this recursive expression regex101.com/r/Hlt37z/2 seems to work don't know if recursive expression are supported by preg_replace
– Nahuel Fouilleul
Nov 12 '18 at 8:25
this recursive expression regex101.com/r/Hlt37z/2 seems to work don't know if recursive expression are supported by preg_replace
– Nahuel Fouilleul
Nov 12 '18 at 8:25
add a comment |
2 Answers
2
active
oldest
votes
Such regex matches only outter brackets
^(((([^()]|(?1))*)))
and replace with
^{$2}
demo on regex101
demo on sandbox
answered Nov 12 '18 at 8:36
splash58
21k21225
OP wants to match^before(
– anubhava
Nov 12 '18 at 8:38
1
@anubhava Thanks, updated
– splash58
Nov 12 '18 at 8:41
Worked nicely in my test: regex101.com/r/tMlAzv/10 (one line is a non-match on purpose)
– Kai Noack
Nov 12 '18 at 10:12
Glad to help! Good luck!
– splash58
Nov 12 '18 at 10:13
add a comment |
You can use this recursive regex in PHP with a negative lookahead:
$str = 'this should be transformed a^(x²) and this b^(-(x²))';
$re = '/^ ( ( ( (?: [^()]* | (?-2) )* ) ) ) (?!.*^()/x';
$repl = preg_replace($re, '^{$2}', $str);
//=> this should be transformed a^(x²) and this b^{-(x²)}
RegEx Demo
answered Nov 12 '18 at 8:36
anubhava
520k46316390
add a comment |
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2 Answers
2
active
oldest
votes
2 Answers
2
active
oldest
votes
active
oldest
votes
active
oldest
votes
Such regex matches only outter brackets
^(((([^()]|(?1))*)))
and replace with
^{$2}
demo on regex101
demo on sandbox
answered Nov 12 '18 at 8:36
splash58
21k21225
OP wants to match^before(
– anubhava
Nov 12 '18 at 8:38
1
@anubhava Thanks, updated
– splash58
Nov 12 '18 at 8:41
Worked nicely in my test: regex101.com/r/tMlAzv/10 (one line is a non-match on purpose)
– Kai Noack
Nov 12 '18 at 10:12
Glad to help! Good luck!
– splash58
Nov 12 '18 at 10:13
add a comment |
Such regex matches only outter brackets
^(((([^()]|(?1))*)))
and replace with
^{$2}
demo on regex101
demo on sandbox
answered Nov 12 '18 at 8:36
splash58
21k21225
OP wants to match^before(
– anubhava
Nov 12 '18 at 8:38
1
@anubhava Thanks, updated
– splash58
Nov 12 '18 at 8:41
Worked nicely in my test: regex101.com/r/tMlAzv/10 (one line is a non-match on purpose)
– Kai Noack
Nov 12 '18 at 10:12
Glad to help! Good luck!
– splash58
Nov 12 '18 at 10:13
add a comment |
Such regex matches only outter brackets
^(((([^()]|(?1))*)))
and replace with
^{$2}
demo on regex101
demo on sandbox
answered Nov 12 '18 at 8:36
splash58
21k21225
Such regex matches only outter brackets
^(((([^()]|(?1))*)))
and replace with
^{$2}
demo on regex101
demo on sandbox
answered Nov 12 '18 at 8:36
splash58
21k21225
edited Nov 12 '18 at 9:14
answered Nov 12 '18 at 8:36
splash58
21k21225
answered Nov 12 '18 at 8:36
splash58
21k21225
answered Nov 12 '18 at 8:36
splash58
21k21225
21k21225
OP wants to match^before(
– anubhava
Nov 12 '18 at 8:38
1
@anubhava Thanks, updated
– splash58
Nov 12 '18 at 8:41
Worked nicely in my test: regex101.com/r/tMlAzv/10 (one line is a non-match on purpose)
– Kai Noack
Nov 12 '18 at 10:12
Glad to help! Good luck!
– splash58
Nov 12 '18 at 10:13
add a comment |
OP wants to match^before(
– anubhava
Nov 12 '18 at 8:38
1
@anubhava Thanks, updated
– splash58
Nov 12 '18 at 8:41
Worked nicely in my test: regex101.com/r/tMlAzv/10 (one line is a non-match on purpose)
– Kai Noack
Nov 12 '18 at 10:12
Glad to help! Good luck!
– splash58
Nov 12 '18 at 10:13
OP wants to match
^ before (– anubhava
Nov 12 '18 at 8:38
OP wants to match
^ before (– anubhava
Nov 12 '18 at 8:38
1
1
@anubhava Thanks, updated
– splash58
Nov 12 '18 at 8:41
@anubhava Thanks, updated
– splash58
Nov 12 '18 at 8:41
Worked nicely in my test: regex101.com/r/tMlAzv/10 (one line is a non-match on purpose)
– Kai Noack
Nov 12 '18 at 10:12
Worked nicely in my test: regex101.com/r/tMlAzv/10 (one line is a non-match on purpose)
– Kai Noack
Nov 12 '18 at 10:12
Glad to help! Good luck!
– splash58
Nov 12 '18 at 10:13
Glad to help! Good luck!
– splash58
Nov 12 '18 at 10:13
add a comment |
You can use this recursive regex in PHP with a negative lookahead:
$str = 'this should be transformed a^(x²) and this b^(-(x²))';
$re = '/^ ( ( ( (?: [^()]* | (?-2) )* ) ) ) (?!.*^()/x';
$repl = preg_replace($re, '^{$2}', $str);
//=> this should be transformed a^(x²) and this b^{-(x²)}
RegEx Demo
answered Nov 12 '18 at 8:36
anubhava
520k46316390
add a comment |
You can use this recursive regex in PHP with a negative lookahead:
$str = 'this should be transformed a^(x²) and this b^(-(x²))';
$re = '/^ ( ( ( (?: [^()]* | (?-2) )* ) ) ) (?!.*^()/x';
$repl = preg_replace($re, '^{$2}', $str);
//=> this should be transformed a^(x²) and this b^{-(x²)}
RegEx Demo
answered Nov 12 '18 at 8:36
anubhava
520k46316390
add a comment |
You can use this recursive regex in PHP with a negative lookahead:
$str = 'this should be transformed a^(x²) and this b^(-(x²))';
$re = '/^ ( ( ( (?: [^()]* | (?-2) )* ) ) ) (?!.*^()/x';
$repl = preg_replace($re, '^{$2}', $str);
//=> this should be transformed a^(x²) and this b^{-(x²)}
RegEx Demo
answered Nov 12 '18 at 8:36
anubhava
520k46316390
You can use this recursive regex in PHP with a negative lookahead:
$str = 'this should be transformed a^(x²) and this b^(-(x²))';
$re = '/^ ( ( ( (?: [^()]* | (?-2) )* ) ) ) (?!.*^()/x';
$repl = preg_replace($re, '^{$2}', $str);
//=> this should be transformed a^(x²) and this b^{-(x²)}
RegEx Demo
answered Nov 12 '18 at 8:36
anubhava
520k46316390
answered Nov 12 '18 at 8:36
anubhava
520k46316390
answered Nov 12 '18 at 8:36
anubhava
520k46316390
answered Nov 12 '18 at 8:36
anubhava
520k46316390
520k46316390
add a comment |
add a comment |
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Regular expressions typically have problems with all kinds of nested structures.
– Some programmer dude
Nov 12 '18 at 8:15
What is expected output for
this should be transformed a^(x²) and this b^(-(x²))?– anubhava
Nov 12 '18 at 8:22
1
this recursive expression regex101.com/r/Hlt37z/2 seems to work don't know if recursive expression are supported by preg_replace
– Nahuel Fouilleul
Nov 12 '18 at 8:25