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Top Forums Shell Programming and Scripting Regex issue with \s in character class. Post 303042656 by Scrutinizer on Thursday 2nd of January 2020 08:56:49 AM
Old 01-02-2020
Quote:
Originally Posted by Neo
Also, another FWIW:

Code:
linux# php -a
Interactive mode enabled

php > $a = ' FOO ';
php > echo preg_match('/[\s][A-Z]+[\s]/', $a,$matches);
1
php > echo $matches[0];
 FOO 
php >

so, it works in a PHP REGEX .....
POSIX regular expressions (BRE/ERE) and the GNU and BSD derivatives are the exception, rather than the norm, in that \ is not special/meta within a character class (bracket) expression.

In (I think all) other regex flavours \ is special in a character class (bracket) expression.


--
Shortcuts like \s are not part of POSIX BRE/ERE, but are supported as an extension in BSD and GNU implementations.

Last edited by Scrutinizer; 01-02-2020 at 10:04 AM..
 

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Returns the name of the previously defined output handler callback, or FALSE if no handler was previously defined. EXAMPLES
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