From c31967d43ae0790e536fde04594c523a35a58bba Mon Sep 17 00:00:00 2001
From: Joseph Edwards <josephdavidedwards@gmail.com>
Date: Tue, 2 Jul 2024 14:25:42 +0100
Subject: [PATCH] Add note to inverses documentation

---
 include/libsemigroups/presentation.hpp | 5 +++++
 1 file changed, 5 insertions(+)

diff --git a/include/libsemigroups/presentation.hpp b/include/libsemigroups/presentation.hpp
index b54385541..eb9b5dfaa 100644
--- a/include/libsemigroups/presentation.hpp
+++ b/include/libsemigroups/presentation.hpp
@@ -2162,6 +2162,11 @@ namespace libsemigroups {
     //! * the alphabet contains duplicate letters
     //! * the inverses do not act as semigroup inverses
     //!
+    //! \note
+    //! Whilst the alphabet is not specified as an argument to this function, it
+    //! is necessary to validate the alphabet here; a specification of inverses
+    //! cannot make sense if the alphabet contains duplicate letters.
+    //!
     //! \sa
     //! * \ref Presentation<Word>::validate_alphabet
     //! * \ref presentation::validate_semigroup_inverses