boostorg · jll63 · Aug 23, 2026 · Aug 23, 2026 · Aug 23, 2026 · Aug 23, 2026
@@ -288,6 +288,40 @@ grep -rn "\`'" doc/modules/ROOT/pages/*.adoc    # must return nothing
 After building, no stray backticks should survive outside code blocks —
 `grep -n '\`' doc/html/openmethod/<page>.html` should only hit backticks inside C++ comments.
 
+### Reference (MrDocs) constraints
+
+MrDocs turns the condition of an `enable_if_t` used as a defaulted template argument into a C++20
+requires-clause by copying the **raw source text** spanning the condition expression - it does not
+walk the expression tree (cppalliance/mrdocs#1016, which upstream cannot fix until MrDocs can
+manipulate expression trees). `BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)`, which hides the
+`detail::` qualification of the exposition-only traits, therefore disappears only when it sits
+*before* the first token of the condition: it expands to nothing under `__MRDOCS__`, so it falls
+outside the copied range. Anywhere inside the condition - after a `!`, after a `&&`, inside
+parentheses - its name is printed verbatim, whatever shape the macro has (function-like as here,
+object-like, or a bare `#ifndef __MRDOCS__` around `detail::`). That is why a constraint with two
+occurrences renders the first one correctly and leaks the second.
+
+Two rules keep the reference clean; the long-form version lives next to the macro definition in
+`core.hpp`:
+
+- **The macro must be the first thing in the condition.** Spell a negation
+  `BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::) Trait<T> == false`, never `!... Trait<T>`.
+- **One trait per condition.** When a constraint needs several, give each its own defaulted
+  template parameter. MrDocs joins them with `&&`, in order, so the rendered clause is unchanged -
+  and substitution short-circuits at the first failure, so a dependent type in a later condition
+  (`typename Other::element_type`) is only formed once the earlier ones pass.
+
+Between them these cover every constraint in the library, so **do not declare a member twice**, an
+unqualified copy under `#ifdef __MRDOCS__` beside the real one. Only MrDocs ever compiles that
+copy, so the two drift apart silently and the reference then documents a constraint the library
+does not have. The `#ifdef __MRDOCS__` blocks that remain remove declarations from the reference
+(friends, deleted overloads, the `VirtualTraits` blueprint) rather than restate them.
+
+Only expressions are affected: types are printed from the AST, so the macro may appear anywhere in
+one (`method::operator()` takes
+`typename BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::) StripVirtualDecorator<Parameters>::type...` and
+renders correctly). After a doc build, `grep -rl MRDOCS doc/html/` must return nothing.
+
 ## Common Development Patterns
 
 ### Working with Shared Libraries / DLL Support
@@ -379,6 +413,19 @@ For examples:
 4. For changes affecting examples: enable `BOOST_OPENMETHOD_BUILD_EXAMPLES`
 5. Submit PRs against the `develop` branch
 
+### Posting in public on the maintainer's behalf
+
+Anything published under the maintainer's account - a GitHub issue or comment, a PR body, a
+mailing-list or forum post - must **identify its author in the text itself**, on the first line:
+
+```
+*(Written by Claude Code, on behalf of @jll63.)*
+```
+
+The account is a person's, and readers reasonably assume a human wrote what it says; an unlabelled
+post misrepresents who is speaking, and a signature in the tool call or the commit trailer is not
+visible to them. Ask before posting anyway - the attribution line does not substitute for consent.
+
 ## Important Implementation Details
 
 ### Static Registration

@@ -33,6 +33,7 @@ include-macros:
   - 'BOOST_OPENMETHOD*'
 exclude-macros:
   - 'BOOST_OPENMETHOD_DETAIL_*'
+  - 'BOOST_OPENMETHOD_*UNLESS_MRDOCS'
   - 'BOOST_OPENMETHOD_GENSYM'
   - 'BOOST_OPENMETHOD_GUIDE'
 

@@ -66,14 +66,39 @@
 //! Top namespace of the library.
 namespace boost::openmethod {
 
+// Hide the `detail::` qualification of the exposition-only traits from MrDocs,
+// which documents them as members of `boost::openmethod`.
+//
+// MrDocs renders the condition of an `enable_if_t` used as a defaulted template
+// argument as a C++20 requires-clause, by copying the *raw source text* spanning
+// the condition expression - it does not walk the expression tree
+// (cppalliance/mrdocs#1016). A macro is thus elided only when it sits *before*
+// the first token of the condition, where it expands to nothing under
+// `__MRDOCS__` and so falls outside the copied range; anywhere inside the
+// condition - after a `!`, after a `&&`, inside parentheses - its name is
+// printed verbatim. That holds whatever shape the macro has - the function-like
+// form below, an object-like one, or a bare `#ifndef __MRDOCS__` around
+// `detail::`.
+//
+// Hence the rule for a condition mentioning an exposition-only trait:
+//
+// - `BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)` must be the first thing in the
+//   condition. Spell a negation as `Trait<T> == false`, not `!Trait<T>`.
+// - One trait per condition. When a constraint needs several, give each its own
+//   defaulted template parameter - MrDocs joins them with `&&`, in order, so the
+//   rendered clause is unchanged, and substitution short-circuits at the first
+//   failure.
+//
+// Only expressions are affected. Types are printed from the AST, so the macro
+// may appear anywhere in one (see `method::operator()`).
 #ifdef __MRDOCS__
 #define BOOST_OPENMETHOD_OPEN_NAMESPACE_DETAIL_UNLESS_MRDOCS
 #define BOOST_OPENMETHOD_CLOSE_NAMESPACE_DETAIL_UNLESS_MRDOCS
-#define BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+#define BOOST_OPENMETHOD_UNLESS_MRDOCS(...)
 #else
 #define BOOST_OPENMETHOD_OPEN_NAMESPACE_DETAIL_UNLESS_MRDOCS namespace detail {
 #define BOOST_OPENMETHOD_CLOSE_NAMESPACE_DETAIL_UNLESS_MRDOCS }
-#define BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS detail::
+#define BOOST_OPENMETHOD_UNLESS_MRDOCS(...) __VA_ARGS__
 #endif
 
 namespace detail {
@@ -854,7 +879,7 @@ class virtual_ptr {
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 IsPolymorphic<Other, Registry> &&
             std::is_constructible_v<Class*, Other*>>>
     virtual_ptr(Other& other)
@@ -893,7 +918,7 @@ class virtual_ptr {
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 IsPolymorphic<Class, Registry> &&
             std::is_constructible_v<Class*, Other*>>>
     virtual_ptr(Other* other)
@@ -964,7 +989,7 @@ class virtual_ptr {
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 IsPolymorphic<Class, Registry> &&
             std::is_assignable_v<Class*&, Other*>>>
     virtual_ptr& operator=(Other& other) {
@@ -1002,7 +1027,7 @@ class virtual_ptr {
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 IsPolymorphic<Class, Registry> &&
             std::is_assignable_v<Class*&, Other*>>>
     virtual_ptr& operator=(Other* other) {
@@ -1137,8 +1162,8 @@ class virtual_ptr {
 template<class SmartPtr, class Registry>
 class virtual_ptr<
     SmartPtr, Registry,
-    std::enable_if_t<
-        BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS IsSmartPtr<SmartPtr, Registry>>> {
+    std::enable_if_t<BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
+                         IsSmartPtr<SmartPtr, Registry>>> {
 
 #ifndef __MRDOCS__
     template<class, class, typename>
@@ -1202,7 +1227,7 @@ class virtual_ptr<
               detail::box_vptr<use_indirect_vptrs>(detail::null_vptr))),
           obj(std::move(other.obj)) {
     }
-#ifdef __MRDOCS__
+
     //! Construct from a (const) smart pointer to a derived class
     //!
     //! Set the object pointer with a copy of `other`. Set the v-table pointer
@@ -1228,25 +1253,18 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            SameSmartPtr<SmartPtr, Other, Registry> &&
-            IsPolymorphic<typename Other::element_type, Registry> &&
-            std::is_constructible_v<SmartPtr, const Other&>>>
-#else
-    template<
-        class Other,
-        typename = std::enable_if_t<
-            detail::SameSmartPtr<SmartPtr, Other, Registry> &&
-            detail::IsPolymorphic<typename Other::element_type, Registry> &&
-            std::is_constructible_v<SmartPtr, const Other&>>>
-#endif
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
+                SameSmartPtr<SmartPtr, Other, Registry> &&
+            std::is_constructible_v<SmartPtr, const Other&>>,
+        typename = std::enable_if_t<BOOST_OPENMETHOD_UNLESS_MRDOCS(
+            detail::) IsPolymorphic<typename Other::element_type, Registry>>>
     virtual_ptr(const Other& other)
         : vp(detail::box_vptr<use_indirect_vptrs>(
               other ? detail::acquire_vptr<Registry>(*other)
                     : detail::null_vptr)),
           obj(other) {
     }
 
-#if __MRDOCS__
     //! Construct from a smart pointer to a derived class
     //!
     //! Copy object pointer from `other` to `this`. Set the v-table pointer
@@ -1264,25 +1282,18 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            SameSmartPtr<SmartPtr, Other, Registry> &&
-            IsPolymorphic<typename Other::element_type, Registry> &&
-            std::is_constructible_v<SmartPtr, Other&>>>
-#else
-    template<
-        class Other,
-        typename = std::enable_if_t<
-            detail::SameSmartPtr<SmartPtr, Other, Registry> &&
-            detail::IsPolymorphic<typename Other::element_type, Registry> &&
-            std::is_constructible_v<SmartPtr, Other&>>>
-#endif
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
+                SameSmartPtr<SmartPtr, Other, Registry> &&
+            std::is_constructible_v<SmartPtr, Other&>>,
+        typename = std::enable_if_t<BOOST_OPENMETHOD_UNLESS_MRDOCS(
+            detail::) IsPolymorphic<typename Other::element_type, Registry>>>
     virtual_ptr(Other& other)
         : vp(detail::box_vptr<use_indirect_vptrs>(
               other ? detail::acquire_vptr<Registry>(*other)
                     : detail::null_vptr)),
           obj(other) {
     }
 
-#ifdef __MRDOCS__
     //! Move-construct from a smart pointer to a derived class
     //!
     //! Move object pointer from `other` to `this`. Set the v-table pointer
@@ -1307,17 +1318,11 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            SameSmartPtr<SmartPtr, Other, Registry> &&
-            IsPolymorphic<typename Other::element_type, Registry> &&
-            std::is_constructible_v<SmartPtr, Other&&>>>
-#else
-    template<
-        class Other,
-        typename = std::enable_if_t<
-            detail::SameSmartPtr<SmartPtr, Other, Registry> &&
-            detail::IsPolymorphic<typename Other::element_type, Registry> &&
-            std::is_constructible_v<SmartPtr, Other&&>>>
-#endif
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
+                SameSmartPtr<SmartPtr, Other, Registry> &&
+            std::is_constructible_v<SmartPtr, Other&&>>,
+        typename = std::enable_if_t<BOOST_OPENMETHOD_UNLESS_MRDOCS(
+            detail::) IsPolymorphic<typename Other::element_type, Registry>>>
     virtual_ptr(Other&& other)
         : vp(detail::box_vptr<use_indirect_vptrs>(
               other ? detail::acquire_vptr<Registry>(*other)
@@ -1343,7 +1348,7 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 SameSmartPtr<SmartPtr, Other, Registry> &&
             std::is_constructible_v<SmartPtr, const Other&>>>
     virtual_ptr(const virtual_ptr<Other, Registry>& other)
@@ -1376,7 +1381,7 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 SameSmartPtr<SmartPtr, Other, Registry> &&
             std::is_constructible_v<SmartPtr, Other&&>>>
     virtual_ptr(virtual_ptr<Other, Registry>&& other)
@@ -1418,11 +1423,11 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 SameSmartPtr<SmartPtr, Other, Registry> &&
-            std::is_assignable_v<SmartPtr, const Other&> &&
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
-                IsPolymorphic<typename Other::element_type, Registry>>>
+            std::is_assignable_v<SmartPtr, const Other&>>,
+        typename = std::enable_if_t<BOOST_OPENMETHOD_UNLESS_MRDOCS(
+            detail::) IsPolymorphic<typename Other::element_type, Registry>>>
     virtual_ptr& operator=(const Other& other) {
         obj = other;
         vp = detail::box_vptr<use_indirect_vptrs>(
@@ -1454,11 +1459,11 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 SameSmartPtr<SmartPtr, Other, Registry> &&
-            std::is_assignable_v<SmartPtr, Other&&> &&
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
-                IsPolymorphic<typename Other::element_type, Registry>>>
+            std::is_assignable_v<SmartPtr, Other&&>>,
+        typename = std::enable_if_t<BOOST_OPENMETHOD_UNLESS_MRDOCS(
+            detail::) IsPolymorphic<typename Other::element_type, Registry>>>
     virtual_ptr& operator=(Other&& other) {
         vp = detail::box_vptr<use_indirect_vptrs>(
             other ? detail::acquire_vptr<Registry>(*other) : detail::null_vptr);
@@ -1484,7 +1489,7 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 SameSmartPtr<SmartPtr, Other, Registry> &&
             std::is_assignable_v<SmartPtr, Other&>>>
     virtual_ptr& operator=(virtual_ptr<Other, Registry>& other) {
@@ -1513,7 +1518,7 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 SameSmartPtr<SmartPtr, Other, Registry> &&
             std::is_assignable_v<SmartPtr, const Other&>>>
     virtual_ptr& operator=(const virtual_ptr<Other, Registry>& other) {
@@ -1548,7 +1553,7 @@ class virtual_ptr<
     template<
         class Other,
         typename = std::enable_if_t<
-            BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                 SameSmartPtr<SmartPtr, Other, Registry> &&
             std::is_assignable_v<SmartPtr, Other&&>>>
     virtual_ptr& operator=(virtual_ptr<Other, Registry>&& other) {
@@ -2074,7 +2079,7 @@ class method<Id, ReturnType(Parameters...), Registry>
     //! @li @ref ambiguous_call: More than one overrider is applicable, and
     //! none is more specialized than all the others.
     //!
-    auto operator()(typename BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+    auto operator()(typename BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                         StripVirtualDecorator<Parameters>::type... args) const
         -> ReturnType;
 
@@ -2349,7 +2354,7 @@ template<
     typename Id, typename... Parameters, typename ReturnType, class Registry>
 BOOST_FORCEINLINE auto
 method<Id, ReturnType(Parameters...), Registry>::operator()(
-    typename BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+    typename BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
         StripVirtualDecorator<Parameters>::type... args) const -> ReturnType {
     using namespace detail;
     auto pf = resolve(args...);

@@ -180,8 +180,9 @@ class virtual_any {
     template<
         typename T,
         typename = std::enable_if_t<
-            !BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
-                IsVirtualAny<std::decay_t<T>> &&
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
+                IsVirtualAny<std::decay_t<T>> == false>,
+        typename = std::enable_if_t<
             !std::is_same_v<std::decay_t<T>, Any> &&
             std::is_constructible_v<Any, T&&>>>
     virtual_any(T&& value)
@@ -259,8 +260,9 @@ class virtual_any {
     template<
         typename T,
         typename = std::enable_if_t<
-            !BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
-                IsVirtualAny<std::decay_t<T>> &&
+            BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
+                IsVirtualAny<std::decay_t<T>> == false>,
+        typename = std::enable_if_t<
             !std::is_same_v<std::decay_t<T>, Any> &&
             std::is_constructible_v<Any, T&&>>>
     auto operator=(T&& value) -> virtual_any& {
@@ -500,7 +502,7 @@ struct virtual_traits<virtual_any<Any, Registry>&&, Registry> {
 template<class Class, class Registry>
 class virtual_ptr<
     Class, Registry,
-    std::enable_if_t<BOOST_OPENMETHOD_DETAIL_UNLESS_MRDOCS
+    std::enable_if_t<BOOST_OPENMETHOD_UNLESS_MRDOCS(detail::)
                          IsVirtualAny<std::remove_cv_t<Class>>>> {
     static_assert(
         detail::false_t<Class>,