[clang-tools-extra] [clang-tidy][NFC][doc] Improve documentation for modernize-use-equals… (PR #65231)

[Carlos Galvez via cfe-commits]

https://github.com/carlosgalvezp created https://github.com/llvm/llvm-project/pull/65231:

…-delete

So the purpose of the check is more clear. Update examples code to show compliant code.

>From 0ffc7aab2f385babd81b57e8116b0433d85cfaf2 Mon Sep 17 00:00:00 2001
From: =?UTF-8?q?Carlos=20G=C3=A1lvez?= <carlos.galvez at zenseact.com>
Date: Sun, 3 Sep 2023 18:24:55 +0000
Subject: [PATCH] [clang-tidy][NFC][doc] Improve documentation for
 modernize-use-equals-delete

So the purpose of the check is more clear. Update examples code to
show compliant code.
---
 .../checks/modernize/use-equals-delete.rst    | 26 ++++++++++++++-----
 1 file changed, 19 insertions(+), 7 deletions(-)

diff --git a/clang-tools-extra/docs/clang-tidy/checks/modernize/use-equals-delete.rst b/clang-tools-extra/docs/clang-tidy/checks/modernize/use-equals-delete.rst
index c3de904e253802..47de4185667a3e 100644
--- a/clang-tools-extra/docs/clang-tidy/checks/modernize/use-equals-delete.rst
+++ b/clang-tools-extra/docs/clang-tidy/checks/modernize/use-equals-delete.rst
@@ -3,22 +3,34 @@
 modernize-use-equals-delete
 ===========================
 
+Prior to C++11, the only way to "delete" a given function was to make it
+``private`` and without definition, to generate a compiler error (calling
+private function) or a linker error (undefined reference).
+
+After C++11, the more idiomatic way to achieve this is by marking the functions
+as ``= delete``, and keeping them in the ``public`` section.
+
 This check marks unimplemented private special member functions with ``= delete``.
+Additionally, it warns about ``delete``'d functions still kept in the ``private``
+section, that should be moved to the ``public`` one instead.
+
 To avoid false-positives, this check only applies in a translation unit that has
-all other member functions implemented.
+all other member functions implemented. The check will generate partial fixes
+by adding ``= delete``, but the user must manually move it to the ``public``
+section.
 
 .. code-block:: c++
 
-  struct A {
-  private:
+  // Example: bad
+  class A {
+   private:
     A(const A&);
     A& operator=(const A&);
   };
 
-  // becomes
-
-  struct A {
-  private:
+  // Example: good
+  class A {
+   public:
     A(const A&) = delete;
     A& operator=(const A&) = delete;
   };