# Regular expression error **URL:** \ **Category:** Management and Administration\ **Created:** [May 12, 2005, 5:35am UTC](https://community.open-emr.org/t/regular-expression-error/2361 "2005-05-12T05:35:40Z")\ **Posts on this page:** 7\ **Page:** 1
**Author:** ![system](https://discourse-uploads-openemr.s3.dualstack.us-east-1.amazonaws.com/original/2X/b/bb9e4e8ae2ea7faac2e952fd9e38a3ce03aac403.png) [@system](https://community.open-emr.org/u/system)\ **Post date:** [May 12, 2005, 5:35am UTC](https://community.open-emr.org/t/regular-expression-error/2361/1 "2005-05-12T05:35:40Z")
**[ericnormand](https://sourceforge.net/u/ericnormand/)** wrote on [Thursday, May 12, 2005](https://sourceforge.net/p/openemr/discussion/202505/thread/f8376705/#9f93): I’m getting errors that look like they have to do with the \ character in regular expressions.  The two I have encountered so far are openemr/interface/main/myadmin/libraries/common.lib.php line 1082 and openemr/interface/main/myadmin/main.php line 246 Is there a setting I’m missing, because these don’t seem to be bugs that could be passed up. Eric ---
**Author:** ![system](https://discourse-uploads-openemr.s3.dualstack.us-east-1.amazonaws.com/original/2X/b/bb9e4e8ae2ea7faac2e952fd9e38a3ce03aac403.png) [@system](https://community.open-emr.org/u/system)\ **Post date:** [May 12, 2005, 6:31am UTC](https://community.open-emr.org/t/regular-expression-error/2361/2 "2005-05-12T06:31:51Z")
**[sunsetsystems](https://sourceforge.net/u/sunsetsystems/)** wrote on [Thursday, May 12, 2005](https://sourceforge.net/p/openemr/discussion/202505/thread/f8376705/#9f93/c0bf): What version of PHP, and where did the PHP build come from?  It does smell a bit like a PHP bug or build problem. I think Perl-compatible regex’s are more popular.  You could try converting to those if you understand what’s going on. – Rod \ ---
**Author:** ![system](https://discourse-uploads-openemr.s3.dualstack.us-east-1.amazonaws.com/original/2X/b/bb9e4e8ae2ea7faac2e952fd9e38a3ce03aac403.png) [@system](https://community.open-emr.org/u/system)\ **Post date:** [May 14, 2005, 3:14am UTC](https://community.open-emr.org/t/regular-expression-error/2361/3 "2005-05-14T03:14:34Z")
**[ericnormand](https://sourceforge.net/u/ericnormand/)** wrote on [Saturday, May 14, 2005](https://sourceforge.net/p/openemr/discussion/202505/thread/f8376705/#9f93/11ee): It’s php version 4.3.10-2 built for debian. ---
**Author:** ![system](https://discourse-uploads-openemr.s3.dualstack.us-east-1.amazonaws.com/original/2X/b/bb9e4e8ae2ea7faac2e952fd9e38a3ce03aac403.png) [@system](https://community.open-emr.org/u/system)\ **Post date:** [May 15, 2005, 11:01am UTC](https://community.open-emr.org/t/regular-expression-error/2361/4 "2005-05-15T11:01:56Z")
**[sunsetsystems](https://sourceforge.net/u/sunsetsystems/)** wrote on [Sunday, May 15, 2005](https://sourceforge.net/p/openemr/discussion/202505/thread/f8376705/#9f93/b0ca): Looking at [http://www.php.net/manual/en/ref.regex.php](http://www.php.net/manual/en/ref.regex.php), the second “warning” is curious.  It’s as if there are different ways you can build regular expression support and they are not compatible with each other. Just a thought.  I guess what I’d do is play with the regex’s. – Rod \ ---
**Author:** ![system](https://discourse-uploads-openemr.s3.dualstack.us-east-1.amazonaws.com/original/2X/b/bb9e4e8ae2ea7faac2e952fd9e38a3ce03aac403.png) [@system](https://community.open-emr.org/u/system)\ **Post date:** [May 16, 2005, 6:11pm UTC](https://community.open-emr.org/t/regular-expression-error/2361/5 "2005-05-16T18:11:48Z")
**[ericnormand](https://sourceforge.net/u/ericnormand/)** wrote on [Monday, May 16, 2005](https://sourceforge.net/p/openemr/discussion/202505/thread/f8376705/#9f93/3665): I played with the one that gave me the error message and it seemed to work, but another one had a problem.  That’s why the problem seemed more general.  I wouldn’t mind playing with the regex’s, I just don’t know what they are supposed to be matching specifically – I’m afraid of guessing what the regex is trying to do.  Basically with the first one I just made the slash into a triple slash, so it went from “^|[^\]” to “^|[^\\\]”.  But this doesn’t really seem to make much sense as a matcher.  Why put the ^ outside the brackets? I’m also afraid to mess with php regex settings because I have other programs running that are working. Thanks Eric ---
**Author:** ![system](https://discourse-uploads-openemr.s3.dualstack.us-east-1.amazonaws.com/original/2X/b/bb9e4e8ae2ea7faac2e952fd9e38a3ce03aac403.png) [@system](https://community.open-emr.org/u/system)\ **Post date:** [May 16, 2005, 6:16pm UTC](https://community.open-emr.org/t/regular-expression-error/2361/6 "2005-05-16T18:16:56Z")
**[ericnormand](https://sourceforge.net/u/ericnormand/)** wrote on [Monday, May 16, 2005](https://sourceforge.net/p/openemr/discussion/202505/thread/f8376705/#9f93/e4c4): I reread it and thought I wasn’t clear. Basically, I interpreted the original regular expression to mean “the beginning of a string or anything but a back slash”  so I made it three backslashes so that it wouldn’t escape out the bracket when php read the string and when the regex engine got a hold of it.  But I can’t figure out if that is specifically what the programmer had in mind. Eric ---
**Author:** ![system](https://discourse-uploads-openemr.s3.dualstack.us-east-1.amazonaws.com/original/2X/b/bb9e4e8ae2ea7faac2e952fd9e38a3ce03aac403.png) [@system](https://community.open-emr.org/u/system)\ **Post date:** [May 16, 2005, 10:15pm UTC](https://community.open-emr.org/t/regular-expression-error/2361/7 "2005-05-16T22:15:28Z")
**[sunsetsystems](https://sourceforge.net/u/sunsetsystems/)** wrote on [Monday, May 16, 2005](https://sourceforge.net/p/openemr/discussion/202505/thread/f8376705/#9f93/b655): The regex strings that you referred to are single-quoted in the PHP code.  This means that PHP should not be escaping out the bracket.  In theory, ‘\]’ and ‘\\]’ should be identical (the backslash will escape either a single quote or another backslash but nothing else).  ‘\\\]’ will, I guess, be interpreted by PHP as ‘\\]’, as will ‘\\\\]’. So again, I think this is some sort of PHP bug and unfortunately it will take some effort to solve your problem with reasonable confidence. – Rod \