Detect if PCRE was built without the --enable-unicode-properties or --enable-utf8 configuration switches

Question

I\'ve a PHP library that uses a number of regular expressions featuring the \\P expressions for multibyte strings, e.g.

((((?:\\P{M}\\p{M}*)+?)|         


        

Answer 1

While comments suggest checking for PREG_BAD_UTF8_ERROR the PHP source http://lxr.php.net/xref/PHP_5_6/ext/pcre/php_pcre.c#141 suggests this constant is always available if PCRE is. Indeed it seems --enable-unicode-properties is a PCRE lib switch and is simply not exposed by PHP. The only thing I can imagine is running a simple regexp once with warning supressed...

Answer 2

Other than trying it, I think the only way is to use the pcretest command line tool, with the -C option (compile-time options):

bash-4.1.5$ pcretest -C
   No UTF-8 support
   No Unicode properties support
   Newline sequence is LF
   \R matches all Unicode newlines
   Internal link size = 2
   POSIX malloc threshold = 10
   Default match limit = 10000000
   Default recursion depth limit = 10000000
   Match recursion uses stack