From 867d768108eb67a6a51bbdb6c1c3f3a74e4e65c5 Mon Sep 17 00:00:00 2001
From: Danny Robson <danny@nerdcruft.net>
Date: Mon, 15 May 2023 10:32:31 +1000
Subject: [PATCH] debug: add some constexpr/consteval asserts

---
 debug/assert.hpp | 9 +++++++++
 debug/panic.hpp  | 9 +++++++++
 2 files changed, 18 insertions(+)

diff --git a/debug/assert.hpp b/debug/assert.hpp
index 04c91cfe..31173b70 100644
--- a/debug/assert.hpp
+++ b/debug/assert.hpp
@@ -46,6 +46,15 @@
 #endif
 
 
+constexpr void constexpr_assert (auto const &expr)
+{
+    if (std::is_constant_evaluated ())
+        static_cast<bool> (expr) ? void (0) : [] () { throw nullptr; } ();
+    else
+        assert (expr);
+}
+
+
 ///////////////////////////////////////////////////////////////////////////////
 #define SCOPED_SANITY(A) \
 ::cruft::debug::scoped_sanity PASTE(__scoped_sanity_checker,__LINE__) ((A)); \
diff --git a/debug/panic.hpp b/debug/panic.hpp
index be7147b6..a3c3f96a 100644
--- a/debug/panic.hpp
+++ b/debug/panic.hpp
@@ -58,6 +58,15 @@ panic [[noreturn]] (const std::string &msg)
 }
 
 
+template <typename TagT = void>
+constexpr void consteval_panic (void) noexcept {
+    if constexpr (std::is_same_v<TagT, void>) {
+        throw nullptr;
+    }
+}
+
+
+
 ///////////////////////////////////////////////////////////////////////////////
 // not_implemented/unreachable/panic must be callable from constexpr contexts.
 // but they rely on functions that aren't constexpr to perform the controlled