From 332d92ffbeb479bd6e97d6d808951cb21e969ac2 Mon Sep 17 00:00:00 2001
From: jeffro256 <jeffro256@tutanota.com>
Date: Sat, 22 Mar 2025 16:49:21 -0500
Subject: [PATCH] epee: span::operator[] allow mut ref from const span

Changes the `operator[]` method so we can get mutable
references to elements even if the span is `const`.
The operator is now also `constexpr`.
This behavior matches `std::span`.

C++ standard reference: https://en.cppreference.com/w/cpp/container/span/operator_at
---
 contrib/epee/include/span.h | 3 +--
 1 file changed, 1 insertion(+), 2 deletions(-)

diff --git a/contrib/epee/include/span.h b/contrib/epee/include/span.h
index af02d4634..ccc55db53 100644
--- a/contrib/epee/include/span.h
+++ b/contrib/epee/include/span.h
@@ -109,8 +109,7 @@ namespace epee
     constexpr std::size_t size() const noexcept { return len; }
     constexpr std::size_t size_bytes() const noexcept { return size() * sizeof(value_type); }
 
-    T &operator[](size_t idx) noexcept { return ptr[idx]; }
-    const T &operator[](size_t idx) const noexcept { return ptr[idx]; }
+    constexpr T &operator[](size_t idx) const noexcept { return ptr[idx]; }
 
   private:
     T* ptr;