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"
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 const &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;
405class PQXX_LIBEXPORT const_reverse_row_iterator :
private const_row_iterator
408 using super = const_row_iterator;
409 using iterator_type = const_row_iterator;
410 using iterator_type::difference_type;
411 using iterator_type::iterator_category;
412 using iterator_type::pointer;
414 using reference = iterator_type::reference;
416 const_reverse_row_iterator() noexcept = default;
417 const_reverse_row_iterator(const_reverse_row_iterator const &) noexcept =
419 const_reverse_row_iterator(const_reverse_row_iterator &&) noexcept = default;
421 explicit const_reverse_row_iterator(super const &rhs) noexcept :
422 const_row_iterator{rhs}
427 [[nodiscard]] PQXX_PURE iterator_type base() const noexcept;
433 using iterator_type::operator->;
434 using iterator_type::operator*;
441 const_reverse_row_iterator &
442 operator=(const_reverse_row_iterator const &r) noexcept
444 iterator_type::operator=(r);
447 const_reverse_row_iterator operator++() noexcept
449 iterator_type::operator--();
452 const_reverse_row_iterator operator++(
int) &
noexcept;
453 const_reverse_row_iterator &operator--() noexcept
455 iterator_type::operator++();
458 const_reverse_row_iterator operator--(
int) &;
459 const_reverse_row_iterator &operator+=(difference_type i)
noexcept
461 iterator_type::operator-=(i);
464 const_reverse_row_iterator &operator-=(difference_type i)
noexcept
466 iterator_type::operator+=(i);
475 [[nodiscard]] const_reverse_row_iterator
476 operator+(difference_type i)
const noexcept
478 return const_reverse_row_iterator{base() - i};
480 [[nodiscard]] const_reverse_row_iterator
481 operator-(difference_type i)
noexcept
483 return const_reverse_row_iterator{base() + i};
485 [[nodiscard]] difference_type
486 operator-(const_reverse_row_iterator
const &rhs)
const noexcept
488 return rhs.const_row_iterator::operator-(*this);
497 operator==(const_reverse_row_iterator
const &rhs)
const noexcept
499 return iterator_type::operator==(rhs);
502 operator!=(const_reverse_row_iterator
const &rhs)
const noexcept
504 return !operator==(rhs);
507 [[nodiscard]]
constexpr bool
508 operator<(const_reverse_row_iterator
const &rhs)
const noexcept
510 return iterator_type::operator>(rhs);
512 [[nodiscard]]
constexpr bool
513 operator<=(const_reverse_row_iterator
const &rhs)
const noexcept
515 return iterator_type::operator>=(rhs);
517 [[nodiscard]]
constexpr bool
518 operator>(const_reverse_row_iterator
const &rhs)
const noexcept
520 return iterator_type::operator<(rhs);
522 [[nodiscard]]
constexpr bool
523 operator>=(const_reverse_row_iterator
const &rhs)
const noexcept
525 return iterator_type::operator<=(rhs);
532const_row_iterator::operator+(difference_type o)
const noexcept
536 row{home(), idx(), home().columns()},
537 size_type(difference_type(col()) + o)};
540inline const_row_iterator operator+(
541 const_row_iterator::difference_type o, const_row_iterator
const &i)
noexcept
546inline const_row_iterator
547const_row_iterator::operator-(difference_type o)
const noexcept
551 row{home(), idx(), home().columns()},
552 size_type(difference_type(col()) - o)};
555inline const_row_iterator::difference_type
556const_row_iterator::operator-(const_row_iterator
const &i)
const noexcept
558 return difference_type(num() - i.num());
562template<
typename Tuple, std::
size_t index>
563inline void row::extract_value(Tuple &t)
const
566 field
const f{m_result, m_index, index};
Iterator for looped unpacking of a result.
Definition row.hxx:28
Marker-type wrapper: zero-terminated std::string_view.
Definition zview.hxx:38
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:94
std::remove_cv_t< std::remove_reference_t< TYPE > > strip_t
Remove any constness, volatile, and reference-ness from a type.
Definition types.hxx:78
int row_difference_type
Difference between row sizes.
Definition types.hxx:37
T from_string(field const &value)
Convert a field's value to type T.
Definition field.hxx:532