Add init_list and init_ref

include/boost/json/array.hpp

@@ -23,6 +23,7 @@ namespace boost {
 namespace json {
 
 class value;
+class value_ref;
 
 /** A dynamically sized array of JSON values
 
@@ -458,7 +459,7 @@ class array
     */
     BOOST_JSON_DECL
     array(
-        std::initializer_list<value> init,
+        std::initializer_list<value_ref> init,
         storage_ptr sp = {});
 
     //------------------------------------------------------
@@ -535,7 +536,7 @@ class array
     BOOST_JSON_DECL
     array&
     operator=(
-        std::initializer_list<value> init);
+        std::initializer_list<value_ref> init);
 
     //------------------------------------------------------
 
@@ -1271,7 +1272,7 @@ class array
     iterator
     insert(
         const_iterator pos,
-        std::initializer_list<value> init);
+        std::initializer_list<value_ref> init);
 
     /** Insert a constructed element in-place.
 
@@ -1604,10 +1605,6 @@ class array
     void
     copy(array const& other);
 
-    inline
-    void
-    copy(std::initializer_list<value> init);
-
     BOOST_JSON_DECL
     void
     reserve_impl(std::size_t capacity);

include/boost/json/detail/impl/object_impl.ipp

@@ -131,8 +131,6 @@ destroy(
     key_value_pair* p,
     std::size_t n) noexcept
 {
-    if(n == 0)
-        return;
     if(! p->value().storage()->need_free())
         return;
     p += n;

include/boost/json/impl/array.ipp

@@ -38,7 +38,7 @@ undo_insert(
     std::size_t n,
     array& self)
     : self_(self)
-    , n_(static_cast<std::size_t>(n))
+    , n_(n)
     , pos(self.impl_.index_of(pos_))
 {
     if(n > max_size())
@@ -186,12 +186,15 @@ array(
 
 array::
 array(
-    std::initializer_list<value> init,
+    std::initializer_list<value_ref> init,
     storage_ptr sp)
     : sp_(std::move(sp))
 {
     undo_construct u(*this);
-    copy(init);
+    reserve(init.size());
+    value_ref::write_array(
+        data(), init, sp_);
+    impl_.size(init.size());
     u.commit = true;
 }
 
@@ -222,7 +225,7 @@ operator=(array&& other)
 array&
 array::
 operator=(
-    std::initializer_list<value> init)
+    std::initializer_list<value_ref> init)
 {
     array tmp(init, sp_);
     this->~array();
@@ -312,14 +315,14 @@ auto
 array::
 insert(
     const_iterator pos,
-    std::initializer_list<value> init) ->
-        iterator
+    std::initializer_list<
+        value_ref> init) ->
+    iterator
 {
-    undo_insert u(pos,
-        static_cast<std::size_t>(
-            init.size()), *this);
-    for(auto const& v : init)
-        u.emplace(v);
+    undo_insert u(
+        pos, init.size(), *this);
+    value_ref::write_array(
+        impl_.data() + u.pos, init, sp_);
     u.commit = true;
     return impl_.data() + u.pos;
 }
@@ -489,26 +492,6 @@ copy(array const& other)
     }
 }
 
-void
-array::
-copy(
-    std::initializer_list<value> init)
-{
-    if(init.size() > max_size())
-        BOOST_JSON_THROW(
-            std::length_error(
-                "size > max_size()"));
-    reserve(static_cast<
-        std::size_t>(init.size()));
-    for(auto const& v : init)
-    {
-        ::new(
-            impl_.data() +
-            impl_.size()) value(v, sp_);
-        impl_.size(impl_.size() + 1);
-    }
-}
-
 void
 array::
 reserve_impl(std::size_t capacity)

include/boost/json/impl/object.ipp

@@ -160,16 +160,48 @@ object(
 
 object::
 object(
-    init_list init,
+    std::initializer_list<std::pair<
+        key_type, value_ref>> init,
     std::size_t min_capacity,
     storage_ptr sp)
     : sp_(std::move(sp))
 {
     undo_construct u(this);
-    insert_range(
-        init.begin(),
-        init.end(),
-        min_capacity);
+    using FwdIt = std::pair<
+        key_type, value_ref> const*;
+    struct place_impl : place_range
+    {
+        FwdIt it;
+        std::size_t n;
+        storage_ptr const& sp;
+
+        place_impl(
+            FwdIt it_,
+            std::size_t n_,
+            storage_ptr const& sp_)
+            : it(it_)
+            , n(n_)
+            , sp(sp_)
+        {
+        }
+
+        bool
+        operator()(void* dest) override
+        {
+            if(n-- == 0)
+                return false;
+            ::new(dest) value_type(
+                it->first,
+                it->second.make_value(sp));
+            ++it;
+            return true;
+        }
+    };
+    if( min_capacity < init.size())
+        min_capacity = init.size();
+    place_impl f(
+        init.begin(), init.size(), sp_);
+    insert_range_impl(min_capacity, f);
     u.self = nullptr;
 }
 
@@ -198,7 +230,8 @@ operator=(object const& other)
 object&
 object::
 operator=(
-    init_list init)
+    std::initializer_list<std::pair<
+        key_type, value_ref>> init)
 {
     object tmp(init, sp_);
     this->~object();
@@ -221,12 +254,47 @@ clear() noexcept
 
 void
 object::
-insert(init_list init)
+insert(
+    std::initializer_list<std::pair<
+        key_type, value_ref>> init)
 {
-    insert_range(
-        init.begin(),
-        init.end(),
-        init.size());
+    using FwdIt = std::pair<
+        key_type, value_ref> const*;
+    struct place_impl : place_range
+    {
+        FwdIt it;
+        std::size_t n;
+        storage_ptr const& sp;
+
+        place_impl(
+            FwdIt it_,
+            std::size_t n_,
+            storage_ptr const& sp_)
+            : it(it_)
+            , n(n_)
+            , sp(sp_)
+        {
+        }
+
+        bool
+        operator()(void* dest) override
+        {
+            if(n-- == 0)
+                return false;
+            ::new(dest) value_type(
+                it->first,
+                it->second.make_value(sp));
+            ++it;
+            return true;
+        }
+    };
+    auto const n0 = size();
+    if(init.size() > max_size() - n0)
+        BOOST_JSON_THROW(
+            detail::object_too_large_exception());
+    place_impl f(
+        init.begin(), init.size(), sp_);
+    insert_range_impl(n0 + init.size(), f);
 }
 
 auto