gtsam/gtsam/base/utilities.h

58 lines
1.7 KiB
C++

#pragma once
#include <string>
#include <iostream>
#include <sstream>
namespace gtsam {
/**
* For Python __str__().
* Redirect std cout to a string stream so we can return a string representation
* of an object when it prints to cout.
* https://stackoverflow.com/questions/5419356/redirect-stdout-stderr-to-a-string
*/
struct RedirectCout {
/// constructor -- redirect stdout buffer to a stringstream buffer
RedirectCout() : ssBuffer_(), coutBuffer_(std::cout.rdbuf(ssBuffer_.rdbuf())) {}
/// return the string
std::string str() const;
/// destructor -- redirect stdout buffer to its original buffer
~RedirectCout();
private:
std::stringstream ssBuffer_;
std::streambuf* coutBuffer_;
};
}
namespace gtsam {
// Adapted from https://stackoverflow.com/a/32223343/9151520
// An adaptation of boost::mp11::index_sequence
template <size_t... Ints>
struct index_sequence {
using type = index_sequence;
using value_type = size_t;
static constexpr std::size_t size() noexcept { return sizeof...(Ints); }
};
namespace detail {
template <class Sequence1, class Sequence2>
struct _merge_and_renumber;
template <size_t... I1, size_t... I2>
struct _merge_and_renumber<index_sequence<I1...>, index_sequence<I2...>>
: index_sequence<I1..., (sizeof...(I1) + I2)...> {};
} // namespace detail
template <size_t N>
struct make_index_sequence : detail::_merge_and_renumber<typename make_index_sequence<N / 2>::type,
typename make_index_sequence<N - N / 2>::type> {};
template <>
struct make_index_sequence<0> : index_sequence<> {};
template <>
struct make_index_sequence<1> : index_sequence<0> {};
template <class... T>
using index_sequence_for = make_index_sequence<sizeof...(T)>;
} // namespace gtsam