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// Copyright 2009-present MongoDB, Inc.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
// http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.
#include <map>
#include <vector>
#include <bsoncxx/builder/stream/array.hpp>
#include <bsoncxx/builder/stream/document.hpp>
#include <bsoncxx/json.hpp>
#include <examples/macros.hh>
using namespace bsoncxx;
// concatenates arbitrary ranges into an array context
template <typename begin_t, typename end_t>
class range_array_appender {
public:
range_array_appender(begin_t begin, end_t end)
: _begin(std::move(begin)), _end(std::move(end)) {}
void operator()(bsoncxx::builder::stream::array_context<> ac) const {
for (auto iter = _begin; iter != _end; ++iter) {
ac = ac << *iter;
}
}
private:
begin_t _begin;
end_t _end;
};
template <typename begin_t, typename end_t>
range_array_appender<begin_t, end_t> make_range_array_appender(begin_t&& begin, end_t&& end) {
return range_array_appender<begin_t, end_t>(std::forward<begin_t>(begin),
std::forward<end_t>(end));
}
// concatenates arbitrary ranges into an key context
template <typename begin_t, typename end_t>
class range_kvp_appender {
public:
range_kvp_appender(begin_t begin, end_t end) : _begin(std::move(begin)), _end(std::move(end)) {}
void operator()(bsoncxx::builder::stream::key_context<> ac) const {
for (auto iter = _begin; iter != _end; ++iter) {
ac = ac << iter->first << iter->second;
}
}
private:
begin_t _begin;
end_t _end;
};
template <typename begin_t, typename end_t>
range_kvp_appender<begin_t, end_t> make_range_kvp_appender(begin_t&& begin, end_t&& end) {
return range_kvp_appender<begin_t, end_t>(std::forward<begin_t>(begin),
std::forward<end_t>(end));
}
int EXAMPLES_CDECL main() {
using builder::stream::array;
using builder::stream::document;
using builder::stream::finalize;
// bsoncxx::builder::stream presents an iostream like interface for succinctly
// constructing complex BSON objects. It also allows for interesting
// primitives by writing your own callables with interesting signatures.
// Some key value pairs we'd like to append
std::map<std::string, int> some_kvps = {{"a", 1}, {"b", 2}, {"c", 3}};
// Adapt our kvps
auto doc = document() << make_range_kvp_appender(some_kvps.begin(), some_kvps.end())
<< finalize;
// Now doc = {
// "a" : 1,
// "b" : 2,
// "c" : 3
// }
// Some values we'd like to append;
std::vector<int> some_numbers = {1, 2, 3};
// Adapt our values
auto arr = array() << make_range_array_appender(some_numbers.begin(), some_numbers.end())
<< finalize;
// Now arr = {
// "0" : 1,
// "1" : 2,
// "2" : 3
// }
}
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