Renamed ./src/external to ./src/extensions. No code logic changes. (0.40.5)

web/documentation/extensions/pcre2/pcre2.md

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+---
+layout: page
+published: true
+noToc: false
+noComments: false
+noDate: false
+title: Fun - PCRE2 (Perl-Compatible Regex) extension (optional)
+subtitle: Documentation for PCRE2 (Perl-Compatible Regex) extension (optional)
+description: Documentation for PCRE2 (Perl-Compatible Regex) extension (optional)
+permalink: /documentation/extensions/pcre2/
+lang: en
+tags:
+- compatible
+- extension
+- optional
+- pcre2
+- perl
+- regex
+---
+
+
+- CMake option: FUN_WITH_PCRE2=ON
+- Purpose: Advanced regular expressions via PCRE2.
+- Homepage: [https://www.pcre.org/](https://www.pcre.org/){:class="ext"}
+
+## Opcodes:
+
+- OP_PCRE2_TEST: pops flags, text, pattern; pushes 1/0
+- OP_PCRE2_MATCH: pops flags, text, pattern; pushes match map or Nil
+- OP_PCRE2_FINDALL: pops flags, text, pattern; pushes array of match maps
+
+## Notes:
+
+- Requires PCRE2 development headers/libs.
+- Flags are backend-specific; see implementation for supported bits.