refactor: [WIP] define ValueFrom overloads for Info types

include/mrdocs/Dom/Value.hpp

@@ -113,14 +113,6 @@ class MRDOCS_DECL
 
     Value(char c) noexcept : Value(std::string_view(&c, 1)) {}
 
-    template<class Enum>
-    requires
-        std::is_enum_v<Enum> &&
-        (!std::same_as<Enum, dom::Kind>)
-    Value(Enum v) noexcept
-        : Value(static_cast<std::underlying_type_t<Enum>>(v))
-    {}
-
     template<std::size_t N>
     Value(char const(&sz)[N])
         : Value(String(sz))
@@ -800,6 +792,45 @@ ValueFrom(T&& t)
     return v;
 }
 
+/** Convert an object of type `T` to @ref dom::Value with a context
+
+    This function attempts to convert an object
+    of type `T` to @ref dom::Value using
+
+    @li a user-provided overload of `tag_invoke`.
+
+    @li one of @ref dom::Value's constructors,
+
+    Conversion of other types is done by calling an overload of `tag_invoke`
+    found by argument-dependent lookup. Its signature should be similar to:
+
+    @code
+    void tag_invoke( ValueFromTag, dom::Value&, T );
+    @endcode
+
+    @par Exception Safety
+    Strong guarantee.
+
+    @tparam T The type of the object to convert.
+
+    @param t The object to convert.
+
+    @return @ref dom::Value out parameter.
+
+    @see @ref dom::ValueFromTag,
+    <a href="http://www.open-std.org/jtc1/sc22/wg21/docs/papers/2019/p1895r0.pdf">
+        tag_invoke: A general pattern for supporting customisable functions</a>
+*/
+template <class T, class Context>
+requires HasValueFrom<T, Context>
+Value
+ValueFrom(T&& t, Context const& ctx)
+{
+    dom::Value v;
+    ValueFrom(static_cast<T&&>(t), ctx, v);
+    return v;
+}
+
 } // dom
 
 template <std::convertible_to<std::string_view> SV>

include/mrdocs/Metadata/Function.hpp

@@ -67,6 +67,19 @@ enum class FunctionClass
 
 MRDOCS_DECL dom::String toString(FunctionClass kind) noexcept;
 
+/** Return the FunctionClass from a @ref dom::Value string.
+ */
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    FunctionClass kind)
+{
+    v = toString(kind);
+}
+
+
 // KRYSTIAN TODO: attributes (nodiscard, deprecated, and carries_dependency)
 // KRYSTIAN TODO: flag to indicate whether this is a function parameter pack
 /** Represents a single function parameter */

include/mrdocs/Metadata/Info.hpp

@@ -47,6 +47,18 @@ MRDOCS_DECL
 dom::String
 toString(InfoKind kind) noexcept;
 
+/** Return the InfoKind from a @ref dom::Value string.
+ */
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    InfoKind kind)
+{
+    v = toString(kind);
+}
+
 /** Base class with common properties of all symbols
 */
 struct MRDOCS_VISIBLE

include/mrdocs/Metadata/Name.hpp

@@ -113,6 +113,23 @@ MRDOCS_DECL
 std::string
 toString(const NameInfo& N);
 
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    NameInfo const& I,
+    DomCorpus const* domCorpus);
+
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    std::unique_ptr<NameInfo> const& I,
+    DomCorpus const* domCorpus);
+
+
 } // mrdocs
 } // clang
 

include/mrdocs/Metadata/Record.hpp

@@ -56,6 +56,16 @@ enum class RecordKeyKind
 
 MRDOCS_DECL dom::String toString(RecordKeyKind kind) noexcept;
 
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    RecordKeyKind kind)
+{
+    v = toString(kind);
+}
+
 /** Metadata for struct, class, or union.
 */
 struct RecordInfo
@@ -92,6 +102,24 @@ struct RecordInfo
     }
 };
 
+constexpr
+std::string_view
+getDefaultAccessString(
+    RecordInfo const& I) noexcept
+{
+    switch(I.KeyKind)
+    {
+    case RecordKeyKind::Class:
+        return "private";
+    case RecordKeyKind::Struct:
+    case RecordKeyKind::Union:
+        return "public";
+    default:
+        MRDOCS_UNREACHABLE();
+    }
+}
+
+
 } // mrdocs
 } // clang
 

include/mrdocs/Metadata/Specifiers.hpp

@@ -229,6 +229,54 @@ toString(
     bool resolved = false,
     bool implicit = false);
 
+/** Return the AccessKind as a @ref dom::Value string.
+ */
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    AccessKind kind)
+{
+    v = toString(kind);
+}
+
+/** Return the ConstexprKind as a @ref dom::Value string.
+ */
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    ConstexprKind kind)
+{
+    v = toString(kind);
+}
+
+/** Return the StorageClassKind as a @ref dom::Value string.
+ */
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    StorageClassKind kind)
+{
+    v = toString(kind);
+}
+
+/** Return the ReferenceKind as a @ref dom::Value string.
+ */
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    ReferenceKind kind)
+{
+    v = toString(kind);
+}
+
 } // mrdocs
 } // clang
 

include/mrdocs/Metadata/Symbols.hpp

@@ -19,6 +19,15 @@
 #include <cstring>
 #include <compare>
 #include <string_view>
+#include <memory>
+
+namespace clang::mrdocs {
+    class DomCorpus;
+    namespace dom {
+        struct ValueFromTag;
+        class Value;
+    }
+}
 
 namespace clang {
 namespace mrdocs {
@@ -151,6 +160,35 @@ compareSymbolNames(
     std::string_view symbolName0,
     std::string_view symbolName1) noexcept;
 
+/** Convert SymbolID to dom::Value string in the DOM using toBase16
+ */
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    SymbolID const& id);
+
+/** Convert SymbolID to dom::Value object in the DOM using Corpus
+ */
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    SymbolID const& id,
+    DomCorpus const* domCorpus);
+
+/** Convert SymbolID pointers to dom::Value or null.
+ */
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    std::unique_ptr<SymbolID> const& t,
+    DomCorpus const* domCorpus);
+
 } // mrdocs
 } // clang
 

include/mrdocs/Metadata/Template.hpp

@@ -36,6 +36,16 @@ enum class TArgKind : int
 
 MRDOCS_DECL std::string_view toString(TArgKind kind) noexcept;
 
+inline
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    TArgKind kind)
+{
+    v = toString(kind);
+}
+
 struct TArg
 {
     /** The kind of template argument this is. */
@@ -133,6 +143,22 @@ visit(
 
 MRDOCS_DECL std::string toString(const TArg& arg) noexcept;
 
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    TArg const& I,
+    DomCorpus const* domCorpus);
+
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    std::unique_ptr<TArg> const& I,
+    DomCorpus const* domCorpus);
+
 // ----------------------------------------------------------------
 
 enum class TParamKind : int
@@ -176,6 +202,21 @@ struct TParam
     }
 };
 
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    TParam const& I,
+    DomCorpus const* domCorpus);
+
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    std::unique_ptr<TParam> const& I,
+    DomCorpus const* domCorpus);
+
+
 template<TParamKind K>
 struct IsTParam : TParam
 {
@@ -307,6 +348,23 @@ struct TemplateInfo
     }
 };
 
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    TemplateInfo const& I,
+    DomCorpus const* domCorpus);
+
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    std::unique_ptr<TemplateInfo> const& I,
+    DomCorpus const* domCorpus);
+
+
 } // mrdocs
 } // clang
 

include/mrdocs/Metadata/Type.hpp

@@ -285,6 +285,23 @@ toString(
     const TypeInfo& T,
     std::string_view Name = "");
 
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    TypeInfo const& I,
+    DomCorpus const* domCorpus);
+
+MRDOCS_DECL
+void
+tag_invoke(
+    dom::ValueFromTag,
+    dom::Value& v,
+    std::unique_ptr<TypeInfo> const& I,
+    DomCorpus const* domCorpus);
+
+
 } // mrdocs
 } // clang