Add example/parse_into_canada.cpp

example/CMakeLists.txt

@@ -10,6 +10,7 @@
 source_group("" FILES
     file.hpp
     parse_into.cpp
+    parse_into_canada.cpp
     path.cpp
     pretty.cpp
     proxy.cpp
@@ -24,6 +25,12 @@ add_executable(parse_into
 set_property(TARGET parse_into PROPERTY FOLDER "example")
 target_link_libraries(parse_into PRIVATE Boost::json)
 
+add_executable(parse_into_canada
+    parse_into_canada.cpp
+)
+set_property(TARGET parse_into_canada PROPERTY FOLDER "example")
+target_link_libraries(parse_into_canada PRIVATE Boost::json)
+
 #
 
 add_executable(path

example/Jamfile

@@ -13,6 +13,8 @@ exe path : path.cpp ;
 
 exe parse_into : parse_into.cpp ;
 
+exe parse_into_canada : parse_into_canada.cpp ;
+
 exe pretty : pretty.cpp ;
 
 exe proxy : proxy.cpp ;

example/parse_into_canada.cpp

@@ -0,0 +1,98 @@
+//
+// Copyright (c) 2021 Peter Dimov
+//
+// Distributed under the Boost Software License, Version 1.0. (See accompanying
+// file LICENSE_1_0.txt or copy at http://www.boost.org/LICENSE_1_0.txt)
+//
+// Official repository: https://github.com/boostorg/json
+//
+
+//
+// An example that compares the performance of json::parse and
+// json::parse_into on canada.json
+//
+
+#include <boost/json.hpp>
+
+#if BOOST_CXX_VERSION < 201400L || ( defined(BOOST_MSVC) && BOOST_MSVC < 1910 )
+
+#include <boost/config/pragma_message.hpp>
+
+BOOST_PRAGMA_MESSAGE( "This example requires C++14 or VS2017 or later" )
+
+int main() {}
+
+#else
+
+#include <boost/describe.hpp>
+
+#include <chrono>
+#include <fstream>
+#include <iostream>
+#include <iterator>
+#include <map>
+#include <utility>
+#include <vector>
+
+struct geometry_type
+{
+    std::string type;
+    std::vector< std::vector<std::pair<double, double>> > coordinates;
+};
+
+BOOST_DESCRIBE_STRUCT(geometry_type, (), (type, coordinates))
+
+struct feature
+{
+    std::string type;
+    std::map<std::string, std::string> properties;
+    geometry_type geometry;
+};
+
+BOOST_DESCRIBE_STRUCT(feature, (), (type, properties, geometry))
+
+struct canada
+{
+    std::string type;
+    std::vector<feature> features;
+};
+
+BOOST_DESCRIBE_STRUCT(canada, (), (type, features))
+
+using namespace std::chrono_literals;
+
+int main()
+{
+    std::ifstream is( "canada.json" );
+    std::string json( std::istreambuf_iterator<char>( is ), std::istreambuf_iterator<char>{} );
+
+    std::cout << "canada.json: " << json.size() << " bytes\n";
+
+    {
+        auto tp1 = std::chrono::steady_clock::now();
+
+        boost::json::value jv = boost::json::parse( json );
+
+        auto tp2 = std::chrono::steady_clock::now();
+        std::cout << "boost::json::parse: " << (tp2 - tp1) / 1ms << " ms\n";
+    }
+
+    {
+        auto tp1 = std::chrono::steady_clock::now();
+
+        canada w;
+
+        boost::json::error_code ec;
+        boost::json::parse_into( w, json, ec );
+
+        if( ec.failed() )
+        {
+            std::cout << "Error: " << ec.what() << std::endl;
+        }
+
+        auto tp2 = std::chrono::steady_clock::now();
+        std::cout << "parse_into<canada>: " << (tp2 - tp1) / 1ms << " ms\n";
+    }
+}
+
+#endif