SchemaDocument: Copy constructor

[cviebig]

Hello @miloyip,

thank you for merging the Validator branch so fast.

I'm about to use it now and found a difference in behauvior of Document and SchemaDocument where I wonder if this is important. To me it seems that the copy constructor of SchemaDocument is implicitly deleted while Document maybe copied. Did I perceive this correctly? Alternatively I can of course use smart pointers, but just being curious, thus asking here :) So feel free to close it without much explanations please.

#include <rapidjson/document.h>
#include <rapidjson/schema.h>

::rapidjson::Document
load_json_from_file(
        const std::string& path_to_file) {
    std::string json = readFileContent(path_to_file);
    ::rapidjson::Document document;
    document.Parse(json.c_str());
    return document;
}

::rapidjson::SchemaDocument
load_schema_from_file(const std::string& path_to_file) {
    ::rapidjson::Document const& document =
        load_json_from_file(path_to_file);
    return ::rapidjson::SchemaDocument(document);
}

Stacktrace:

SchemaDocument const& schema = load_schema_from_file(schema_file);
Document const& document = load_json_from_file(path_to_file);

json_parser.cpp: In function ‘rapidjson::SchemaDocument load_schema_from_file(const string&)’:
json_parser.cpp:1397:52: error: use of deleted function ‘rapidjson::GenericSchemaDocument<rapidjson::GenericValue<rapidjson::UTF8<> > >::GenericSchemaDocument(const rapidjson::GenericSchemaDocument<rapidjson::GenericValue<rapidjson::UTF8<> > >&)’
         return ::rapidjson::SchemaDocument(document);
                                                    ^
In file included from json_validator.hpp:7:0,
                 from json_parser.cpp:42:
/usr/include/rapidjson/schema.h:1304:7: note: ‘rapidjson::GenericSchemaDocument<rapidjson::GenericValue<rapidjson::UTF8<> > >::GenericSchemaDocument(const rapidjson::GenericSchemaDocument<rapidjson::GenericValue<rapidjson::UTF8<> > >&)’ is implicitly deleted because the default definition would be ill-formed:
 class GenericSchemaDocument {
       ^
In file included from /usr/include/rapidjson/reader.h:23:0,
                 from /usr/include/rapidjson/document.h:20,
                 from json_parser.cpp:13:
/usr/include/rapidjson/internal/stack.h:212:5: error: ‘rapidjson::internal::Stack<Allocator>::Stack(const rapidjson::internal::Stack<Allocator>&) [with Allocator = rapidjson::CrtAllocator]’ is private
     Stack(const Stack&);
     ^
In file included from json_validator.hpp:7:0,
                 from json_parser.cpp:42:
/usr/include/rapidjson/schema.h:1304:7: error: within this context
 class GenericSchemaDocument {
       ^
In file included from /usr/include/rapidjson/reader.h:23:0,
                 from /usr/include/rapidjson/document.h:20,
                 from json_parser.cpp:13:
/usr/include/rapidjson/internal/stack.h:212:5: error: ‘rapidjson::internal::Stack<Allocator>::Stack(const rapidjson::internal::Stack<Allocator>&) [with Allocator = rapidjson::CrtAllocator]’ is private
     Stack(const Stack&);
     ^
In file included from json_validator.hpp:7:0,
                 from json_parser.cpp:42:
/usr/include/rapidjson/schema.h:1304:7: error: within this context
 class GenericSchemaDocument {
       ^
ninja: build stopped: subcommand failed.

[miloyip]

It is actually due to that Document supports move constructor in C++11.
I have added the move constructor for SchemaDocument in PR #554.

[cviebig]

Cool, thank you :)