16#if !defined(PQXX_HEADER_PRE)
17# error "Include libpqxx headers as <pqxx/header>, not <pqxx/header.hxx>."
20#include "pqxx/except.hxx"
21#include "pqxx/field.hxx"
22#include "pqxx/result.hxx"
24#include "pqxx/internal/concat.hxx"
28template<
typename... T>
class result_iter;
46class PQXX_LIBEXPORT row
53 using const_iterator = const_row_iterator;
54 using iterator = const_iterator;
55 using reference = field;
56 using pointer = const_row_iterator;
57 using const_reverse_iterator = const_reverse_row_iterator;
58 using reverse_iterator = const_reverse_iterator;
60 row() noexcept = default;
61 row(row &&) noexcept = default;
62 row(row const &) noexcept = default;
63 row &operator=(row const &) noexcept = default;
64 row &operator=(row &&) noexcept = default;
70 [[nodiscard]] PQXX_PURE
bool operator==(row const &) const noexcept;
71 [[nodiscard]]
bool operator!=(row const &rhs) const noexcept
73 return not operator==(rhs);
77 [[nodiscard]] const_iterator begin() const noexcept;
78 [[nodiscard]] const_iterator cbegin() const noexcept;
79 [[nodiscard]] const_iterator end() const noexcept;
80 [[nodiscard]] const_iterator cend() const noexcept;
86 [[nodiscard]] reference front() const noexcept;
87 [[nodiscard]] reference back() const noexcept;
89 [[nodiscard]] const_reverse_row_iterator rbegin() const noexcept;
90 [[nodiscard]] const_reverse_row_iterator crbegin() const noexcept;
91 [[nodiscard]] const_reverse_row_iterator rend() const noexcept;
92 [[nodiscard]] const_reverse_row_iterator crend() const noexcept;
94 [[nodiscard]] reference operator[](size_type) const noexcept;
98 [[nodiscard]] reference operator[](zview col_name) const;
100 reference at(size_type) const;
104 reference at(zview col_name) const;
106 [[nodiscard]] constexpr size_type size() const noexcept
108 return m_end - m_begin;
112 [[nodiscard]]
constexpr result::size_type rownumber() const noexcept
122 [[nodiscard]] size_type column_number(zview col_name)
const;
125 [[nodiscard]]
oid column_type(size_type)
const;
128 [[nodiscard]]
oid column_type(zview col_name)
const
130 return column_type(column_number(col_name));
134 [[nodiscard]]
oid column_table(size_type col_num)
const;
137 [[nodiscard]]
oid column_table(zview col_name)
const
139 return column_table(column_number(col_name));
150 [[nodiscard]] size_type table_column(size_type)
const;
153 [[nodiscard]] size_type table_column(zview col_name)
const
155 return table_column(column_number(col_name));
159 [[nodiscard]]
constexpr result::size_type num() const noexcept
173 template<
typename Tuple>
void to(Tuple &t)
const
175 check_size(std::tuple_size_v<Tuple>);
188 template<
typename... TYPE> std::tuple<TYPE...> as()
const
190 check_size(
sizeof...(TYPE));
191 using seq = std::make_index_sequence<
sizeof...(TYPE)>;
192 return get_tuple<std::tuple<TYPE...>>(seq{});
195 [[deprecated(
"Swap iterators, not rows.")]]
void swap(row &)
noexcept;
208 [[deprecated(
"Row slicing is going away. File a bug if you need it.")]] row
209 slice(size_type sbegin, size_type send)
const;
212 [[nodiscard, deprecated(
"Row slicing is going away.")]] PQXX_PURE
bool
213 empty() const noexcept;
216 friend class const_row_iterator;
218 row(result r, result_size_type index, size_type cols) noexcept;
221 void check_size(size_type expected)
const
223 if (size() != expected)
224 throw usage_error{internal::concat(
225 "Tried to extract ", expected,
" field(s) from a row of ", size(),
233 template<
typename TUPLE> TUPLE as_tuple()
const
235 using seq = std::make_index_sequence<std::tuple_size_v<TUPLE>>;
236 return get_tuple<TUPLE>(seq{});
241 template<
typename Tuple>
void convert(Tuple &t)
const
243 extract_fields(t, std::make_index_sequence<std::tuple_size_v<Tuple>>{});
256 result::size_type m_index = 0;
260 size_type m_begin = 0;
265 template<
typename Tuple, std::size_t... indexes>
266 void extract_fields(Tuple &t, std::index_sequence<indexes...>)
const
268 (extract_value<Tuple, indexes>(t), ...);
271 template<
typename Tuple, std::
size_t index>
272 void extract_value(Tuple &t)
const;
275 template<
typename TUPLE, std::size_t... indexes>
276 auto get_tuple(std::index_sequence<indexes...>)
const
278 return std::make_tuple(get_field<TUPLE, indexes>()...);
282 template<
typename TUPLE, std::
size_t index>
auto get_field()
const
284 return (*
this)[index].as<std::tuple_element_t<index, TUPLE>>();
290class PQXX_LIBEXPORT const_row_iterator :
public field
293 using iterator_category = std::random_access_iterator_tag;
295 using pointer = field
const *;
298 using reference = field;
300#include "pqxx/internal/ignore-deprecated-pre.hxx"
301 const_row_iterator() noexcept = default;
302#include "pqxx/internal/ignore-deprecated-post.hxx"
303 const_row_iterator(row
const &t, row_size_type c) noexcept :
304 field{t.m_result, t.m_index, c}
306 const_row_iterator(field
const &F) noexcept : field{F} {}
307 const_row_iterator(const_row_iterator
const &)
noexcept =
default;
308 const_row_iterator(const_row_iterator &&) noexcept = default;
314 [[nodiscard]] constexpr pointer operator->() const noexcept {
return this; }
315 [[nodiscard]] reference operator*() const noexcept {
return {*
this}; }
322 const_row_iterator &operator=(const_row_iterator
const &)
noexcept =
default;
323 const_row_iterator &operator=(const_row_iterator &&) noexcept = default;
325 const_row_iterator operator++(
int) & noexcept;
326 const_row_iterator &operator++() noexcept
331 const_row_iterator operator--(
int) &
noexcept;
332 const_row_iterator &operator--() noexcept
338 const_row_iterator &operator+=(difference_type i)
noexcept
340 m_col = size_type(difference_type(m_col) + i);
343 const_row_iterator &operator-=(difference_type i)
noexcept
345 m_col = size_type(difference_type(m_col) - i);
354 [[nodiscard]]
constexpr bool
355 operator==(const_row_iterator
const &i)
const noexcept
357 return col() == i.col();
359 [[nodiscard]]
constexpr bool
360 operator!=(const_row_iterator
const &i)
const noexcept
362 return col() != i.col();
364 [[nodiscard]]
constexpr bool
365 operator<(const_row_iterator
const &i)
const noexcept
367 return col() < i.col();
369 [[nodiscard]]
constexpr bool
370 operator<=(const_row_iterator
const &i)
const noexcept
372 return col() <= i.col();
374 [[nodiscard]]
constexpr bool
375 operator>(const_row_iterator
const &i)
const noexcept
377 return col() > i.col();
379 [[nodiscard]]
constexpr bool
380 operator>=(const_row_iterator
const &i)
const noexcept
382 return col() >= i.col();
390 [[nodiscard]]
inline const_row_iterator
391 operator+(difference_type)
const noexcept;
393 friend const_row_iterator
394 operator+(difference_type, const_row_iterator
const &)
noexcept;
396 [[nodiscard]]
inline const_row_iterator
397 operator-(difference_type)
const noexcept;
398 [[nodiscard]]
inline difference_type
399 operator-(const_row_iterator
const &)
const noexcept;
401 [[nodiscard]]
inline field operator[](difference_type offset)
const noexcept
403 return *(*
this + offset);
410class PQXX_LIBEXPORT const_reverse_row_iterator :
private const_row_iterator
413 using super = const_row_iterator;
414 using iterator_type = const_row_iterator;
415 using iterator_type::difference_type;
416 using iterator_type::iterator_category;
417 using iterator_type::pointer;
419 using reference = iterator_type::reference;
421 const_reverse_row_iterator() noexcept = default;
422 const_reverse_row_iterator(const_reverse_row_iterator const &) noexcept =
424 const_reverse_row_iterator(const_reverse_row_iterator &&) noexcept = default;
426 explicit const_reverse_row_iterator(super const &rhs) noexcept :
427 const_row_iterator{rhs}
432 [[nodiscard]] PQXX_PURE iterator_type base() const noexcept;
438 using iterator_type::operator->;
439 using iterator_type::operator*;
446 const_reverse_row_iterator &
447 operator=(const_reverse_row_iterator const &r) noexcept
449 iterator_type::operator=(r);
452 const_reverse_row_iterator operator++() noexcept
454 iterator_type::operator--();
457 const_reverse_row_iterator operator++(
int) &
noexcept;
458 const_reverse_row_iterator &operator--() noexcept
460 iterator_type::operator++();
463 const_reverse_row_iterator operator--(
int) &;
464 const_reverse_row_iterator &operator+=(difference_type i)
noexcept
466 iterator_type::operator-=(i);
469 const_reverse_row_iterator &operator-=(difference_type i)
noexcept
471 iterator_type::operator+=(i);
480 [[nodiscard]] const_reverse_row_iterator
481 operator+(difference_type i)
const noexcept
483 return const_reverse_row_iterator{base() - i};
485 [[nodiscard]] const_reverse_row_iterator
486 operator-(difference_type i)
noexcept
488 return const_reverse_row_iterator{base() + i};
490 [[nodiscard]] difference_type
491 operator-(const_reverse_row_iterator
const &rhs)
const noexcept
493 return rhs.const_row_iterator::operator-(*this);
495 [[nodiscard]]
inline field operator[](difference_type offset)
const noexcept
497 return *(*
this + offset);
506 operator==(const_reverse_row_iterator
const &rhs)
const noexcept
508 return iterator_type::operator==(rhs);
511 operator!=(const_reverse_row_iterator
const &rhs)
const noexcept
513 return !operator==(rhs);
516 [[nodiscard]]
constexpr bool
517 operator<(const_reverse_row_iterator
const &rhs)
const noexcept
519 return iterator_type::operator>(rhs);
521 [[nodiscard]]
constexpr bool
522 operator<=(const_reverse_row_iterator
const &rhs)
const noexcept
524 return iterator_type::operator>=(rhs);
526 [[nodiscard]]
constexpr bool
527 operator>(const_reverse_row_iterator
const &rhs)
const noexcept
529 return iterator_type::operator<(rhs);
531 [[nodiscard]]
constexpr bool
532 operator>=(const_reverse_row_iterator
const &rhs)
const noexcept
534 return iterator_type::operator<=(rhs);
541const_row_iterator::operator+(difference_type o)
const noexcept
545 row{home(), idx(), home().columns()},
546 size_type(difference_type(col()) + o)};
549inline const_row_iterator operator+(
550 const_row_iterator::difference_type o, const_row_iterator
const &i)
noexcept
555inline const_row_iterator
556const_row_iterator::operator-(difference_type o)
const noexcept
560 row{home(), idx(), home().columns()},
561 size_type(difference_type(col()) - o)};
564inline const_row_iterator::difference_type
565const_row_iterator::operator-(const_row_iterator
const &i)
const noexcept
567 return difference_type(num() - i.num());
571template<
typename Tuple, std::
size_t index>
572inline void row::extract_value(Tuple &t)
const
574 using field_type = strip_t<decltype(std::get<index>(t))>;
575 field
const f{m_result, m_index, index};
576 std::get<index>(t) = from_string<field_type>(f);
Iterator for looped unpacking of a result.
Definition result_iter.hxx:27
Internal items for libpqxx' own use. Do not use these yourself.
Definition encodings.cxx:33
The home of all libpqxx classes, functions, templates, etc.
Definition array.cxx:27
unsigned int oid
PostgreSQL database row identifier.
Definition libpq-forward.hxx:33
int row_size_type
Number of fields in a row of database data.
Definition types.hxx:34
strip_t< decltype(*std::begin(std::declval< CONTAINER >()))> value_type
The type of a container's elements.
Definition types.hxx:96
int row_difference_type
Difference between row sizes.
Definition types.hxx:37