The maximum length of a compiled pattern is approximately 64K data units (bytes -for the 8-bit library, 32-bit units for the 32-bit library, and 32-bit units for -the 32-bit library) if PCRE is compiled with the default internal linkage size -of 2 bytes. If you want to process regular expressions that are truly enormous, +for the 8-bit library, 16-bit units for the 16-bit library, and 32-bit units for +the 32-bit library) if PCRE is compiled with the default internal linkage size, +which is 2 bytes for the 8-bit and 16-bit libraries, and 4 bytes for the 32-bit +library. If you want to process regular expressions that are truly enormous, you can compile PCRE with an internal linkage size of 3 or 4 (when building the 16-bit or 32-bit library, 3 is rounded up to 4). See the README file in the source distribution and the @@ -36,7 +37,10 @@ All values in repeating quantifiers must be less than
There is no limit to the number of parenthesized subpatterns, but there can be -no more than 65535 capturing subpatterns. +no more than 65535 capturing subpatterns. There is, however, a limit to the +depth of nesting of parenthesized subpatterns of all kinds. This is imposed in +order to limit the amount of system stack used at compile time. The limit can +be specified when PCRE is built; the default is 250.
There is a limit to the number of forward references to subsequent subpatterns @@ -50,7 +54,7 @@ maximum number of named subpatterns is 10000.
The maximum length of a name in a (*MARK), (*PRUNE), (*SKIP), or (*THEN) verb -is 255 for the 8-bit library and 65535 for the 16-bit and 32-bit library. +is 255 for the 8-bit library and 65535 for the 16-bit and 32-bit libraries.
The maximum length of a subject string is the largest positive number that an
@@ -77,9 +81,9 @@ Cambridge CB2 3QH, England.
REVISION
-Last updated: 04 May 2012
+Last updated: 05 November 2013
-Copyright © 1997-2012 University of Cambridge.
+Copyright © 1997-2013 University of Cambridge.
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