From 9ead4aeea9ee26fc141d2a87be8e2f3551b32539 Mon Sep 17 00:00:00 2001
From: Peter Dimov <pdimov@gmail.com>
Date: Sat, 21 Feb 2026 03:26:49 +0200
Subject: [PATCH] Change operator* and operator-> to throw instead of having a
 precondition

---
 include/boost/system/result.hpp   | 119 +++++++++++++++---------------
 test/result_and_eq_fn1r.cpp       |   6 +-
 test/result_and_fn1r.cpp          |  20 ++---
 test/result_and_mfn1r.cpp         |  12 +--
 test/result_convert_construct.cpp |   6 +-
 test/result_emplace.cpp           |   9 +++
 test/result_or_eq_fn0r.cpp        |  18 ++---
 test/result_or_eq_fn0v.cpp        |   6 +-
 test/result_or_eq_value.cpp       |   8 +-
 test/result_or_fn0r.cpp           |  18 ++---
 test/result_value_access.cpp      |  90 +++++++++++++++-------
 test/result_value_construct.cpp   |  11 ++-
 test/result_value_construct2.cpp  |   9 +++
 test/result_value_construct3.cpp  |  13 +++-
 test/result_value_construct6.cpp  |  11 ++-
 test/result_value_construct7.cpp  |  13 +++-
 16 files changed, 228 insertions(+), 141 deletions(-)

diff --git a/include/boost/system/result.hpp b/include/boost/system/result.hpp
index ba3b486..20ff010 100644
--- a/include/boost/system/result.hpp
+++ b/include/boost/system/result.hpp
@@ -205,7 +205,7 @@ public:
     {
         if( r2 )
         {
-            v_.template emplace<0>( *r2 );
+            v_.template emplace<0>( r2.unsafe_value() );
         }
     }
 
@@ -224,7 +224,7 @@ public:
     {
         if( r2 )
         {
-            v_.template emplace<0>( std::move( *r2 ) );
+            v_.template emplace<0>( std::move( r2 ).unsafe_value() );
         }
     }
 
@@ -317,73 +317,69 @@ public:
 
 #endif
 
-    // unchecked value access
+    // checked value access
 
-    BOOST_CXX14_CONSTEXPR T* operator->() noexcept
+    BOOST_CXX14_CONSTEXPR T* operator->()
     {
-        return variant2::get_if<0>( &v_ );
+        return &value();
     }
 
-    BOOST_CXX14_CONSTEXPR T const* operator->() const noexcept
+    BOOST_CXX14_CONSTEXPR T const* operator->() const
     {
-        return variant2::get_if<0>( &v_ );
+        return &value();
     }
 
 #if defined( BOOST_NO_CXX11_REF_QUALIFIERS )
 
-    BOOST_CXX14_CONSTEXPR T& operator*() noexcept
+    BOOST_CXX14_CONSTEXPR T& operator*()
     {
-        BOOST_ASSERT( has_value() );
-        return *operator->();
+        return value();
     }
 
-    BOOST_CXX14_CONSTEXPR T const& operator*() const noexcept
+    BOOST_CXX14_CONSTEXPR T const& operator*() const
     {
-        BOOST_ASSERT( has_value() );
-        return *operator->();
+        return value();
     }
 
 #else
 
-    BOOST_CXX14_CONSTEXPR T& operator*() & noexcept
+    BOOST_CXX14_CONSTEXPR T& operator*() &
     {
-        BOOST_ASSERT( has_value() );
-        return *operator->();
+        return value();
     }
 
-    BOOST_CXX14_CONSTEXPR T const& operator*() const & noexcept
+    BOOST_CXX14_CONSTEXPR T const& operator*() const &
     {
-        BOOST_ASSERT( has_value() );
-        return *operator->();
+        return value();
     }
 
     template<class U = T>
         BOOST_CXX14_CONSTEXPR
         typename std::enable_if<std::is_move_constructible<U>::value, T>::type
-        operator*() && noexcept(std::is_nothrow_move_constructible<T>::value)
+        operator*() &&
     {
-        return std::move(**this);
+        return std::move( value() );
     }
 
     template<class U = T>
         BOOST_CXX14_CONSTEXPR
         typename std::enable_if<!std::is_move_constructible<U>::value, T&&>::type
-        operator*() && noexcept
+        operator*() &&
     {
-        return std::move(**this);
+        return std::move( value() );
     }
 
     template<class U = T>
         BOOST_CXX14_CONSTEXPR
         typename std::enable_if<std::is_move_constructible<U>::value, T>::type
-        operator*() const && noexcept = delete;
+        operator*() const && = delete;
 
     template<class U = T>
         BOOST_CXX14_CONSTEXPR
         typename std::enable_if<!std::is_move_constructible<U>::value, T const&&>::type
-        operator*() const && noexcept
+        operator*() const &&
     {
-        return std::move(**this);
+        return std::move( value() );
     }
 
 #endif
@@ -514,7 +510,7 @@ template<class Ch, class Tr, class T, class E> std::basic_ostream<Ch, Tr>& opera
 {
     if( r.has_value() )
     {
-        os << "value:" << *r;
+        os << "value:" << r.unsafe_value();
     }
     else
     {
@@ -645,21 +641,23 @@ public:
         }
     }
 
-    // unchecked value access
+    // checked value access
 
-    BOOST_CXX14_CONSTEXPR void* operator->() noexcept
+    BOOST_CXX14_CONSTEXPR void* operator->()
     {
-        return variant2::get_if<0>( &v_ );
+        value();
+        return &variant2::unsafe_get<0>( v_ );
     }
 
-    BOOST_CXX14_CONSTEXPR void const* operator->() const noexcept
+    BOOST_CXX14_CONSTEXPR void const* operator->() const
     {
-        return variant2::get_if<0>( &v_ );
+        value();
+        return &variant2::unsafe_get<0>( v_ );
     }
 
-    BOOST_CXX14_CONSTEXPR void operator*() const noexcept
+    BOOST_CXX14_CONSTEXPR void operator*() const
     {
-        BOOST_ASSERT( has_value() );
+        return value();
     }
 
     // unchecked value access
@@ -854,7 +852,7 @@ public:
     {
         if( r2 )
         {
-            this->emplace( *r2 );
+            this->emplace( r2.unsafe_value() );
         }
     }
 
@@ -889,17 +887,16 @@ public:
         }
     }
 
-    // unchecked value access
+    // checked value access
 
-    BOOST_CXX14_CONSTEXPR U* operator->() const noexcept
+    BOOST_CXX14_CONSTEXPR U* operator->() const
     {
-        return has_value()? variant2::unsafe_get<0>( v_ ): 0;
+        return &value();
     }
 
-    BOOST_CXX14_CONSTEXPR U& operator*() const noexcept
+    BOOST_CXX14_CONSTEXPR U& operator*() const
     {
-        BOOST_ASSERT( has_value() );
-        return *operator->();
+        return value();
     }
 
     // unchecked value access
@@ -952,9 +949,9 @@ public:
     // equality
 
     friend constexpr bool operator==( result const & r1, result const & r2 )
-        noexcept( noexcept( r1 && r2? *r1 == *r2: r1.v_ == r2.v_ ) )
+        noexcept( noexcept( r1 && r2? r1.unsafe_value() == r2.unsafe_value(): r1.v_ == r2.v_ ) )
     {
-        return r1 && r2? *r1 == *r2: r1.v_ == r2.v_;
+        return r1 && r2? r1.unsafe_value() == r2.unsafe_value(): r1.v_ == r2.v_;
     }
 
     friend constexpr bool operator!=( result const & r1, result const & r2 )
@@ -1006,7 +1003,7 @@ operator|( result<T, E> const& r, U&& u )
 {
     if( r )
     {
-        return *r;
+        return r.unsafe_value();
     }
     else
     {
@@ -1022,7 +1019,7 @@ operator|( result<T, E>&& r, U&& u )
 {
     if( r )
     {
-        return *std::move( r );
+        return std::move( r ).unsafe_value();
     }
     else
     {
@@ -1040,7 +1037,7 @@ T operator|( result<T, E> const& r, F&& f )
 {
     if( r )
     {
-        return *r;
+        return r.unsafe_value();
     }
     else
     {
@@ -1056,7 +1053,7 @@ T operator|( result<T, E>&& r, F&& f )
 {
     if( r )
     {
-        return *std::move( r );
+        return std::move( r ).unsafe_value();
     }
     else
     {
@@ -1076,7 +1073,7 @@ operator|( result<T&, E> const& r, F&& f )
 {
     if( r )
     {
-        return *r;
+        return r.unsafe_value();
     }
     else
     {
@@ -1095,7 +1092,7 @@ U operator|( result<T, E> const& r, F&& f )
 {
     if( r )
     {
-        return *r;
+        return r.unsafe_value();
     }
     else
     {
@@ -1112,7 +1109,7 @@ U operator|( result<T, E>&& r, F&& f )
 {
     if( r )
     {
-        return *std::move( r );
+        return std::move( r ).unsafe_value();
     }
     else
     {
@@ -1222,7 +1219,7 @@ result<U, E> operator&( result<T, E>& r, F&& f )
     }
     else
     {
-        return compat::invoke( std::forward<F>( f ), *r );
+        return compat::invoke( std::forward<F>( f ), r.unsafe_value() );
     }
 }
 
@@ -1239,7 +1236,7 @@ result<U, E> operator&( result<T, E> const& r, F&& f )
     }
     else
     {
-        return compat::invoke( std::forward<F>( f ), *r );
+        return compat::invoke( std::forward<F>( f ), r.unsafe_value() );
     }
 }
 
@@ -1256,7 +1253,7 @@ result<U, E> operator&( result<T, E>&& r, F&& f )
     }
     else
     {
-        return compat::invoke( std::forward<F>( f ), *std::move( r ) );
+        return compat::invoke( std::forward<F>( f ), std::move( r ).unsafe_value() );
     }
 }
 
@@ -1273,7 +1270,7 @@ result<U, E> operator&( result<T&, E>&& r, F&& f )
     }
     else
     {
-        return compat::invoke( std::forward<F>( f ), *std::move( r ) );
+        return compat::invoke( std::forward<F>( f ), std::move( r ).unsafe_value() );
     }
 }
 
@@ -1289,7 +1286,7 @@ result<U, E> operator&( result<T, E> const& r, F&& f )
     }
     else
     {
-        compat::invoke( std::forward<F>( f ), *r );
+        compat::invoke( std::forward<F>( f ), r.unsafe_value() );
         return {};
     }
 }
@@ -1306,7 +1303,7 @@ result<U, E> operator&( result<T, E>&& r, F&& f )
     }
     else
     {
-        compat::invoke( std::forward<F>( f ), *std::move( r ) );
+        compat::invoke( std::forward<F>( f ), std::move( r ).unsafe_value() );
         return {};
     }
 }
@@ -1360,7 +1357,7 @@ U operator&( result<T, E>& r, F&& f )
     }
     else
     {
-        return compat::invoke( std::forward<F>( f ), *r );
+        return compat::invoke( std::forward<F>( f ), r.unsafe_value() );
     }
 }
 
@@ -1377,7 +1374,7 @@ U operator&( result<T, E> const& r, F&& f )
     }
     else
     {
-        return compat::invoke( std::forward<F>( f ), *r );
+        return compat::invoke( std::forward<F>( f ), r.unsafe_value() );
     }
 }
 
@@ -1394,7 +1391,7 @@ U operator&( result<T, E>&& r, F&& f )
     }
     else
     {
-        return compat::invoke( std::forward<F>( f ), *std::move( r ) );
+        return compat::invoke( std::forward<F>( f ), std::move( r ).unsafe_value() );
     }
 }
 
@@ -1428,7 +1425,7 @@ result<T, E>& operator&=( result<T, E>& r, F&& f )
 {
     if( r )
     {
-        r = std::forward<F>( f )( *std::move( r ) );
+        r = std::forward<F>( f )( std::move( r ).unsafe_value() );
     }
 
     return r;
@@ -1460,7 +1457,7 @@ result<T, E>& operator&=( result<T, E>& r, F&& f )
 {
     if( r )
     {
-        r = std::forward<F>( f )( *std::move( r ) );
+        r = std::forward<F>( f )( std::move( r ).unsafe_value() );
     }
 
     return r;
diff --git a/test/result_and_eq_fn1r.cpp b/test/result_and_eq_fn1r.cpp
index 703e4dc..535aa76 100644
--- a/test/result_and_eq_fn1r.cpp
+++ b/test/result_and_eq_fn1r.cpp
@@ -96,7 +96,7 @@ int main()
         result<int, E2> r( 1 );
 
         r &= fi;
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( *r, 3 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value(), 3 );
 
         r &= fi2;
         BOOST_TEST( r.has_error() );
@@ -109,7 +109,7 @@ int main()
         result<Y, E2> r( in_place_value, 1 );
 
         r &= fy;
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r->v_, 3 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value().v_, 3 );
 
         r &= fy2;
         BOOST_TEST( r.has_error() );
@@ -123,7 +123,7 @@ int main()
         result<int&, E2> r( x1 );
 
         r &= fri;
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &*r, &*fri( x1 ) );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &r.unsafe_value(), &fri( x1 ).unsafe_value() );
 
         r &= fri2;
         BOOST_TEST( r.has_error() );
diff --git a/test/result_and_fn1r.cpp b/test/result_and_fn1r.cpp
index beaf858..1cfeca8 100644
--- a/test/result_and_fn1r.cpp
+++ b/test/result_and_fn1r.cpp
@@ -112,7 +112,7 @@ int main()
 
         {
             result<int, E2> r2 = r & fi;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 3 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 3 );
         }
 
         {
@@ -131,7 +131,7 @@ int main()
 
         {
             result<int, E2> r2 = r & fi;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 3 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 3 );
         }
 
         {
@@ -147,7 +147,7 @@ int main()
 
     {
         result<int, E2> r2 = result<int, E>( 1 ) & fi;
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 3 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 3 );
     }
 
     {
@@ -216,7 +216,7 @@ int main()
     {
         result<X, E2> r2 = result<Y, E>( in_place_value, 1 ) & fy;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2->v_, 3 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value().v_, 3 );
     }
 
     {
@@ -255,7 +255,7 @@ int main()
 
         {
             result<int, E2> r2 = r & fri;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 3 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 3 );
         }
 
         {
@@ -275,7 +275,7 @@ int main()
 
         {
             result<int, E2> r2 = r & fri;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 3 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 3 );
         }
 
         {
@@ -293,7 +293,7 @@ int main()
         int x1 = 1;
 
         result<int, E2> r2 = result<int&, E>( x1 ) & fri;
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 3 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 3 );
     }
 
     {
@@ -368,7 +368,7 @@ int main()
 
         {
             result<int, E2> r2 = r & fk;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 7 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 7 );
         }
 
         {
@@ -392,7 +392,7 @@ int main()
 
         {
             result<int, E2> r2 = r & fk;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 7 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 7 );
         }
 
         {
@@ -413,7 +413,7 @@ int main()
 
     {
         result<int, E2> r2 = result<void, E>() & fk;
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 7 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 7 );
     }
 
     {
diff --git a/test/result_and_mfn1r.cpp b/test/result_and_mfn1r.cpp
index 46a259e..c98e2a5 100644
--- a/test/result_and_mfn1r.cpp
+++ b/test/result_and_mfn1r.cpp
@@ -41,7 +41,7 @@ int main()
 
         {
             result<int, E2> r2 = r & &X::f;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 1 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 1 );
         }
 
         {
@@ -51,12 +51,12 @@ int main()
 
         {
             result<int&, E2> r2 = r & &X::g;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &r->v_ );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &r.unsafe_value().v_ );
         }
 
         {
             result<int const&, E2> r2 = r & &X::g2;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &r->v_ );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &r.unsafe_value().v_ );
         }
 
         {
@@ -75,7 +75,7 @@ int main()
 
         {
             result<int, E2> r2 = r & &X::f;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 1 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 1 );
         }
 
         {
@@ -85,7 +85,7 @@ int main()
 
         {
             result<int const&, E2> r2 = r & &X::g2;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &r->v_ );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &r.unsafe_value().v_ );
         }
 
         {
@@ -102,7 +102,7 @@ int main()
     {
         {
             result<int, E2> r2 = result<X, E>( 1 ) & &X::f;
-            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( *r2, 1 );
+            BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( r2.unsafe_value(), 1 );
         }
 
         {
diff --git a/test/result_convert_construct.cpp b/test/result_convert_construct.cpp
index 39bbcb6..4bcdcea 100644
--- a/test/result_convert_construct.cpp
+++ b/test/result_convert_construct.cpp
@@ -126,7 +126,7 @@ int main()
         result<char const*, int> r( "test" );
         result<std::string, X> r2 = r;
 
-        BOOST_TEST( r2 ) && BOOST_TEST_EQ( *r2, std::string( "test" ) );
+        BOOST_TEST( r2 ) && BOOST_TEST_EQ( r2.unsafe_value(), std::string( "test" ) );
         BOOST_TEST_EQ( X::instances, 0 );
     }
 
@@ -136,7 +136,7 @@ int main()
         result<char const*, int> const r( "test" );
         result<std::string, X> r2 = r;
 
-        BOOST_TEST( r2 ) && BOOST_TEST_EQ( *r2, std::string( "test" ) );
+        BOOST_TEST( r2 ) && BOOST_TEST_EQ( r2.unsafe_value(), std::string( "test" ) );
         BOOST_TEST_EQ( X::instances, 0 );
     }
 
@@ -145,7 +145,7 @@ int main()
     {
         result<std::string, X> r2 = result<char const*, int>( "test" );
 
-        BOOST_TEST( r2 ) && BOOST_TEST_EQ( *r2, std::string( "test" ) );
+        BOOST_TEST( r2 ) && BOOST_TEST_EQ( r2.unsafe_value(), std::string( "test" ) );
         BOOST_TEST_EQ( X::instances, 0 );
     }
 
diff --git a/test/result_emplace.cpp b/test/result_emplace.cpp
index 784d924..77e1b14 100644
--- a/test/result_emplace.cpp
+++ b/test/result_emplace.cpp
@@ -42,6 +42,15 @@ struct Y
 
 int Y::instances = 0;
 
+struct E
+{
+};
+
+BOOST_NORETURN void throw_exception_from_error( Y const &, boost::source_location const& )
+{
+    throw E();
+}
+
 int main()
 {
     {
diff --git a/test/result_or_eq_fn0r.cpp b/test/result_or_eq_fn0r.cpp
index b333081..f6b3c47 100644
--- a/test/result_or_eq_fn0r.cpp
+++ b/test/result_or_eq_fn0r.cpp
@@ -87,11 +87,11 @@ int main()
 
         r |= fi;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value(), 1 );
 
         r |= fi2;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value(), 1 );
     }
 
     {
@@ -103,7 +103,7 @@ int main()
 
         r |= fi;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( *r, 2 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value(), 2 );
     }
 
     {
@@ -111,11 +111,11 @@ int main()
 
         r |= fy;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r->v_, 1 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value().v_, 1 );
 
         r |= fy2;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r->v_, 1 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value().v_, 1 );
     }
 
     {
@@ -127,7 +127,7 @@ int main()
 
         r |= fy;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r->v_, 2 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value().v_, 2 );
     }
 
     {
@@ -137,11 +137,11 @@ int main()
 
         r |= fri;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &*r, &x1 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &r.unsafe_value(), &x1 );
 
         r |= fri2;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &*r, &x1 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &r.unsafe_value(), &x1 );
     }
 
     {
@@ -153,7 +153,7 @@ int main()
 
         r |= fri;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &*r, &*fri() );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &r.unsafe_value(), &fri().unsafe_value() );
     }
 
     return boost::report_errors();
diff --git a/test/result_or_eq_fn0v.cpp b/test/result_or_eq_fn0v.cpp
index 25897d0..bfe2109 100644
--- a/test/result_or_eq_fn0v.cpp
+++ b/test/result_or_eq_fn0v.cpp
@@ -74,7 +74,7 @@ int main()
 
         r |= f;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( *r, 2 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value(), 2 );
     }
 
     {
@@ -90,7 +90,7 @@ int main()
 
         r |= g;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r->v_, 2 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value().v_, 2 );
     }
 
     {
@@ -108,7 +108,7 @@ int main()
 
         r |= h;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &*r, &h() );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &r.unsafe_value(), &h() );
     }
 
     return boost::report_errors();
diff --git a/test/result_or_eq_value.cpp b/test/result_or_eq_value.cpp
index ac2c751..c6e7211 100644
--- a/test/result_or_eq_value.cpp
+++ b/test/result_or_eq_value.cpp
@@ -58,7 +58,7 @@ int main()
 
         r |= 2;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( *r, 2 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value(), 2 );
     }
 
     {
@@ -74,7 +74,7 @@ int main()
 
         r |= X{2};
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r->v_, 2 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( r.unsafe_value().v_, 2 );
     }
 
     {
@@ -85,7 +85,7 @@ int main()
 
         r |= x2;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &*r, &x1 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &r.unsafe_value(), &x1 );
     }
 
     {
@@ -95,7 +95,7 @@ int main()
 
         r |= x2;
 
-        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &*r, &x2 );
+        BOOST_TEST( r.has_value() ) && BOOST_TEST_EQ( &r.unsafe_value(), &x2 );
     }
 
     return boost::report_errors();
diff --git a/test/result_or_fn0r.cpp b/test/result_or_fn0r.cpp
index f8e4191..f678d18 100644
--- a/test/result_or_fn0r.cpp
+++ b/test/result_or_fn0r.cpp
@@ -196,7 +196,7 @@ int main()
 
         auto r2 = r | fri;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &x1 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &x1 );
     }
 
     {
@@ -206,7 +206,7 @@ int main()
 
         auto r2 = r | fri;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &x1 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &x1 );
     }
 
     {
@@ -214,7 +214,7 @@ int main()
 
         auto r2 = result<int&>( x1 ) | fri;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &x1 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &x1 );
     }
 
     {
@@ -224,7 +224,7 @@ int main()
 
         auto r2 = r | fri2;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &x1 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &x1 );
     }
 
     {
@@ -234,7 +234,7 @@ int main()
 
         auto r2 = r | fri2;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &x1 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &x1 );
     }
 
     {
@@ -242,7 +242,7 @@ int main()
 
         auto r2 = result<int&>( x1 ) | fri2;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &x1 );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &x1 );
     }
 
     {
@@ -250,7 +250,7 @@ int main()
 
         auto r2 = r | fri;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &*fri() );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &fri().unsafe_value() );
     }
 
     {
@@ -258,13 +258,13 @@ int main()
 
         auto r2 = r | fri;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &*fri() );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &fri().unsafe_value() );
     }
 
     {
         auto r2 = result<int&, E>( in_place_error ) | fri;
 
-        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &*r2, &*fri() );
+        BOOST_TEST( r2.has_value() ) && BOOST_TEST_EQ( &r2.unsafe_value(), &fri().unsafe_value() );
     }
 
     {
diff --git a/test/result_value_access.cpp b/test/result_value_access.cpp
index 8da97b4..66899a1 100644
--- a/test/result_value_access.cpp
+++ b/test/result_value_access.cpp
@@ -138,7 +138,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -154,7 +155,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -168,7 +170,8 @@ int main()
 
         BOOST_TEST_THROWS( result<int>( ec ).value(), system_error );
 
-        BOOST_TEST_EQ( result<int>( ec ).operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *result<int>( ec ), system_error );
+        BOOST_TEST_THROWS( result<int>( ec ).operator->(), system_error );
     }
 
     {
@@ -184,7 +187,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, std::system_error );
+        BOOST_TEST_THROWS( r.operator->(), std::system_error );
     }
 
     {
@@ -198,7 +202,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -212,7 +217,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, std::system_error );
+        BOOST_TEST_THROWS( r.operator->(), std::system_error );
     }
 
     {
@@ -229,7 +235,8 @@ int main()
         BOOST_TEST_THROWS( r.value(), E2 );
 #endif
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, E2 );
+        BOOST_TEST_THROWS( r.operator->(), E2 );
     }
 
     {
@@ -243,7 +250,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::bad_exception );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, std::bad_exception );
+        BOOST_TEST_THROWS( r.operator->(), std::bad_exception );
     }
 
     {
@@ -303,7 +311,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), E );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<X*>(0) );
+        BOOST_TEST_THROWS( *r, E );
+        BOOST_TEST_THROWS( r.operator->(), E );
     }
 
     {
@@ -319,7 +328,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), E );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<X*>(0) );
+        BOOST_TEST_THROWS( *r, E );
+        BOOST_TEST_THROWS( r.operator->(), E );
     }
 
     {
@@ -333,7 +343,8 @@ int main()
 
         BOOST_TEST_THROWS( (result<X, Y>( ec ).value()), E );
 
-        BOOST_TEST_EQ( (result<X, Y>( ec ).operator->()), static_cast<X*>(0) );
+        BOOST_TEST_THROWS( *(result<X, Y>( ec )), E );
+        BOOST_TEST_THROWS( (result<X, Y>( ec )).operator->(), E );
     }
 
     //
@@ -349,6 +360,9 @@ int main()
 
         BOOST_TEST_NO_THROW( r.value() );
 
+        BOOST_TEST_NO_THROW( *r );
+        BOOST_TEST_NO_THROW( r.operator->() );
+
         BOOST_TEST( r.operator->() != 0 );
     }
 
@@ -363,6 +377,9 @@ int main()
 
         BOOST_TEST_NO_THROW( r.value() );
 
+        BOOST_TEST_NO_THROW( *r );
+        BOOST_TEST_NO_THROW( r.operator->() );
+
         BOOST_TEST( r.operator->() != 0 );
     }
 
@@ -375,6 +392,9 @@ int main()
 
         BOOST_TEST_NO_THROW( result<void>().value() );
 
+        BOOST_TEST_NO_THROW( *result<void>() );
+        BOOST_TEST_NO_THROW( result<void>().operator->() );
+
         BOOST_TEST( result<void>().operator->() != 0 );
     }
 
@@ -391,7 +411,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -407,7 +428,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -421,7 +443,8 @@ int main()
 
         BOOST_TEST_THROWS( result<void>( ec ).value(), system_error );
 
-        BOOST_TEST_EQ( result<void>( ec ).operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *result<void>( ec ), system_error );
+        BOOST_TEST_THROWS( result<void>( ec ).operator->(), system_error );
     }
 
     {
@@ -437,7 +460,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *r, std::system_error );
+        BOOST_TEST_THROWS( r.operator->(), std::system_error );
     }
 
     {
@@ -451,7 +475,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -465,7 +490,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *r, std::system_error );
+        BOOST_TEST_THROWS( r.operator->(), std::system_error );
     }
 
     {
@@ -482,7 +508,8 @@ int main()
         BOOST_TEST_THROWS( r.value(), E2 );
 #endif
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *r, E2 );
+        BOOST_TEST_THROWS( r.operator->(), E2 );
     }
 
     {
@@ -496,7 +523,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::bad_exception );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<void*>(0) );
+        BOOST_TEST_THROWS( *r, std::bad_exception );
+        BOOST_TEST_THROWS( r.operator->(), std::bad_exception );
     }
 
     //
@@ -563,7 +591,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -579,7 +608,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -593,7 +623,8 @@ int main()
 
         BOOST_TEST_THROWS( result<int&>( ec ).value(), system_error );
 
-        BOOST_TEST_EQ( result<int&>( ec ).operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *result<int&>( ec ), system_error );
+        BOOST_TEST_THROWS( result<int&>( ec ).operator->(), system_error );
     }
 
     {
@@ -609,7 +640,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, std::system_error );
+        BOOST_TEST_THROWS( r.operator->(), std::system_error );
     }
 
     {
@@ -623,7 +655,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, system_error );
+        BOOST_TEST_THROWS( r.operator->(), system_error );
     }
 
     {
@@ -637,7 +670,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::system_error );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, std::system_error );
+        BOOST_TEST_THROWS( r.operator->(), std::system_error );
     }
 
     {
@@ -654,7 +688,8 @@ int main()
         BOOST_TEST_THROWS( r.value(), E2 );
 #endif
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, E2 );
+        BOOST_TEST_THROWS( r.operator->(), E2 );
     }
 
     {
@@ -668,7 +703,8 @@ int main()
 
         BOOST_TEST_THROWS( r.value(), std::bad_exception );
 
-        BOOST_TEST_EQ( r.operator->(), static_cast<int*>(0) );
+        BOOST_TEST_THROWS( *r, std::bad_exception );
+        BOOST_TEST_THROWS( r.operator->(), std::bad_exception );
     }
 
     //
diff --git a/test/result_value_construct.cpp b/test/result_value_construct.cpp
index ff2cae4..1ff5680 100644
--- a/test/result_value_construct.cpp
+++ b/test/result_value_construct.cpp
@@ -27,6 +27,15 @@ struct X
 
 int X::instances = 0;
 
+struct E
+{
+};
+
+BOOST_NORETURN void throw_exception_from_error( X const &, boost::source_location const& )
+{
+    throw E();
+}
+
 int main()
 {
     {
@@ -53,7 +62,7 @@ int main()
         BOOST_TEST( r.has_value() );
         BOOST_TEST( !r.has_error() );
 
-        BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST_EQ( r.unsafe_value(), 1 );
     }
 
     BOOST_TEST_EQ( X::instances, 0 );
diff --git a/test/result_value_construct2.cpp b/test/result_value_construct2.cpp
index b3d92a2..eb8584b 100644
--- a/test/result_value_construct2.cpp
+++ b/test/result_value_construct2.cpp
@@ -74,6 +74,15 @@ result<void> fw0()
     return {};
 }
 
+struct E2
+{
+};
+
+BOOST_NORETURN void throw_exception_from_error( E const &, boost::source_location const& )
+{
+    throw E2();
+}
+
 int main()
 {
     {
diff --git a/test/result_value_construct3.cpp b/test/result_value_construct3.cpp
index ebcca2a..841e846 100644
--- a/test/result_value_construct3.cpp
+++ b/test/result_value_construct3.cpp
@@ -26,6 +26,15 @@ struct X
 
 int X::instances = 0;
 
+struct E
+{
+};
+
+BOOST_NORETURN void throw_exception_from_error( X const &, boost::source_location const& )
+{
+    throw E();
+}
+
 int main()
 {
     {
@@ -45,7 +54,7 @@ int main()
         BOOST_TEST( r.has_value() );
         BOOST_TEST( !r.has_error() );
 
-        BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST_EQ( r.unsafe_value(), 1 );
     }
 
     BOOST_TEST_EQ( X::instances, 0 );
@@ -135,7 +144,7 @@ int main()
         BOOST_TEST( r.has_value() );
         BOOST_TEST( !r.has_error() );
 
-        BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST_EQ( r.unsafe_value(), 1 );
     }
 
     return boost::report_errors();
diff --git a/test/result_value_construct6.cpp b/test/result_value_construct6.cpp
index f9dd3fc..18d25c9 100644
--- a/test/result_value_construct6.cpp
+++ b/test/result_value_construct6.cpp
@@ -24,6 +24,15 @@ struct X
 
 int X::instances = 0;
 
+struct E
+{
+};
+
+BOOST_NORETURN void throw_exception_from_error( X const &, boost::source_location const& )
+{
+    throw E();
+}
+
 int main()
 {
     {
@@ -53,7 +62,7 @@ int main()
         BOOST_TEST( r.has_value() );
         BOOST_TEST( !r.has_error() );
 
-        BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST_EQ( r.unsafe_value(), 1 );
     }
 
     BOOST_TEST_EQ( X::instances, 0 );
diff --git a/test/result_value_construct7.cpp b/test/result_value_construct7.cpp
index 97e5343..b0e3ced 100644
--- a/test/result_value_construct7.cpp
+++ b/test/result_value_construct7.cpp
@@ -24,6 +24,15 @@ struct X
 
 int X::instances = 0;
 
+struct E
+{
+};
+
+BOOST_NORETURN void throw_exception_from_error( X const &, boost::source_location const& )
+{
+    throw E();
+}
+
 int main()
 {
     {
@@ -73,7 +82,7 @@ int main()
         BOOST_TEST( r.has_value() );
         BOOST_TEST( !r.has_error() );
 
-        BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST_EQ( r.unsafe_value(), 1 );
     }
 
     {
@@ -83,7 +92,7 @@ int main()
         BOOST_TEST( r.has_value() );
         BOOST_TEST( !r.has_error() );
 
-        BOOST_TEST_EQ( *r, 1 );
+        BOOST_TEST_EQ( r.unsafe_value(), 1 );
     }
 
     BOOST_TEST_EQ( X::instances, 0 );