Merge commit 'f96384a3b596f9bc0a3a035970b09b2c601f0ccb'

docs/content/en/functions/findRe.md

@@ -9,14 +9,25 @@ keywords: [regex]
 signature:
   - "findRE PATTERN INPUT [LIMIT]"
   - "strings.FindRE PATTERN INPUT [LIMIT]"
-relatedfuncs: [replaceRE]
-aliases: []
+relatedfuncs: [findRESubmatch, replaceRE]
 ---
-By default, the `findRE` function finds all matches. You can limit the number of matches with an optional LIMIT parameter.
+By default, `findRE` finds all matches. You can limit the number of matches with an optional LIMIT parameter.
 
 When specifying the regular expression, use a raw [string literal] (backticks) instead of an interpreted string literal (double quotes) to simplify the syntax. With an interpreted string literal you must escape backslashes.
 
-The syntax of the regular expression is the same general syntax used by Perl, Python, and other languages. More precisely, it is the syntax accepted by [RE2] except for `\C`.
+[string literal]: https://go.dev/ref/spec#String_literals
+
+This function uses the [RE2] regular expression library. See the [RE2 syntax documentation] for details. Note that the RE2 `\C` escape sequence is not supported.
+
+[RE2]: https://github.com/google/re2/
+[RE2 syntax documentation]: https://github.com/google/re2/wiki/Syntax/
+
+{{% note %}}
+The RE2 syntax is a subset of that accepted by [PCRE], roughly speaking, and with various [caveats].
+
+[caveats]: https://swtch.com/~rsc/regexp/regexp3.html#caveats
+[PCRE]: https://www.pcre.org/
+{{% /note %}}
 
 This example returns a slice of all second level headings (`h2` elements) within the rendered `.Content`:
 
@@ -35,25 +46,3 @@ To limit the number of matches to one:
 {{% note %}}
 You can write and test your regular expression using [regex101.com](https://regex101.com/). Be sure to select the Go flavor before you begin.
 {{% /note %}}
-
-## findRESubmatch
-
-In Hugo 0.110.0 we added a variant of `findRe` that returns a slice of strings holding the text of the leftmost match of the regular expression in s and the matches, if any, of its subexpressions.
-
-This:
-
-```go-html-template
-{{ findRESubmatch §§<a\s*href="(.+?)">(.+?)</a>§§ §§<li><a href="#foo">Foo</a></li> <li><a href="#bar">Bar</a></li>§§ | print | safeHTML }}
-```
-
-Will print:
-
-```
-[[<a href=\"#foo\">Foo</a> #foo Foo] [<a href=\"#bar\">Bar</a> #bar Bar]]
-```
-
-{{< new-in "0.110.0" >}}
-
-
-[RE2]: https://github.com/google/re2/wiki/Syntax
-[string literal]: https://go.dev/ref/spec#String_literals