From b66f61c21795d0acd49cba0ff03883d2a3714694 Mon Sep 17 00:00:00 2001
From: Gary Talent <gary@drinkingtea.net>
Date: Fri, 10 May 2024 23:55:41 -0500
Subject: [PATCH] [ox/std] Add hash function for UUID

---
 deps/ox/src/ox/std/uuid.hpp | 26 +++++++++++++++++++++++---
 1 file changed, 23 insertions(+), 3 deletions(-)

diff --git a/deps/ox/src/ox/std/uuid.hpp b/deps/ox/src/ox/std/uuid.hpp
index f4a7a899..80b66f1b 100644
--- a/deps/ox/src/ox/std/uuid.hpp
+++ b/deps/ox/src/ox/std/uuid.hpp
@@ -8,9 +8,11 @@
 
 #pragma once
 
+#include "bit.hpp"
 #include "ignore.hpp"
 #include "istring.hpp"
 #include "buffer.hpp"
+#include "hash.hpp"
 #include "random.hpp"
 #include "ranges.hpp"
 #include "stringview.hpp"
@@ -105,7 +107,7 @@ class UUID {
 		static ox::Result<UUID> generate() noexcept;
 
 		[[nodiscard]]
-		constexpr auto value() const noexcept {
+		constexpr auto const&value() const noexcept {
 			return m_value;
 		}
 
@@ -118,8 +120,8 @@ class UUID {
 				return false;
 			} else {
 				constexpr uint64_t zero = 0;
-				return ox::memcmp(&zero, m_value.data() + 0, 8) == 0
-				    && ox::memcmp(&zero, m_value.data() + 8, 8) == 0;
+				return memcmp(&zero, m_value.data() + 0, 8) == 0
+				    && memcmp(&zero, m_value.data() + 8, 8) == 0;
 			}
 		}
 
@@ -192,6 +194,24 @@ class UUID {
 		}
 };
 
+
+template<>
+struct hash<ox::UUID> {
+	[[nodiscard]]
+	constexpr size_t operator()(ox::UUID v) const noexcept {
+		size_t out{};
+		if (std::is_constant_evaluated()) {
+			for (auto i = 0u; i < sizeof(out); ++i) {
+				out |= static_cast<size_t>(v.value()[i]) << (i * 8);
+			}
+		} else {
+			memcpy(&out, &v, sizeof(out));
+		}
+		return out;
+	}
+};
+
+
 template<typename T>
 constexpr Error model(T *io, ox::CommonPtrWith<UUID> auto *obj) noexcept {
 	oxReturnError(io->template setTypeInfo<UUID>());