11 #ifndef PQXX_H_STRCONV
12 #define PQXX_H_STRCONV
14 #if !defined(PQXX_HEADER_PRE)
15 # error "Include libpqxx headers as <pqxx/header>, not <pqxx/header.hxx>."
25 #if __has_include(<charconv>)
29 #if defined(PQXX_HAVE_RANGES) && __has_include(<ranges>)
33 #include "pqxx/except.hxx"
34 #include "pqxx/util.hxx"
35 #include "pqxx/zview.hxx"
81 template<
typename TYPE>
92 template<
typename TYPE,
typename ENABLE =
void>
struct nullness
101 static bool is_null(TYPE
const &value);
109 [[nodiscard]]
static TYPE
null();
140 [[nodiscard]]
static constexpr
bool is_null(TYPE
const &) noexcept
188 [[nodiscard]]
static inline zview
189 to_buf(
char *begin,
char *end, TYPE
const &value);
199 static inline char *
into_buf(
char *begin,
char *end, TYPE
const &value);
215 [[nodiscard]]
static inline std::size_t
250 static constexpr
bool converts_to_string{
false};
251 static constexpr
bool converts_from_string{
false};
254 oops_forbidden_conversion<TYPE>();
256 [[noreturn]]
static char *
into_buf(
char *,
char *, TYPE
const &)
258 oops_forbidden_conversion<TYPE>();
262 oops_forbidden_conversion<TYPE>();
264 [[noreturn]]
static std::size_t
size_buffer(TYPE
const &) noexcept
266 oops_forbidden_conversion<TYPE>();
343 template<
typename ENUM>
372 [[nodiscard]]
static constexpr
zview
373 to_buf(
char *begin,
char *end, ENUM
const &value)
378 static constexpr
char *
into_buf(
char *begin,
char *end, ENUM
const &value)
388 [[nodiscard]]
static std::size_t
size_buffer(ENUM
const &value) noexcept
395 static constexpr
impl_type to_underlying(ENUM
const &value) noexcept
419 #define PQXX_DECLARE_ENUM_CONVERSION(ENUM) \
420 template<> struct string_traits<ENUM> : pqxx::internal::enum_traits<ENUM> \
422 template<> inline std::string_view const type_name<ENUM> \
443 template<
typename TYPE>
458 [[nodiscard]]
inline std::string_view
from_string(std::string_view text)
472 template<
typename T>
inline void from_string(std::string_view text, T &value)
474 value = from_string<T>(text);
484 template<
typename TYPE>
inline std::string
to_string(TYPE
const &value);
495 template<
typename... TYPE>
496 [[nodiscard]]
inline std::vector<std::string_view>
497 to_buf(
char *here,
char const *end, TYPE... value)
499 return {[&here, end](
auto v) {
503 auto len{
static_cast<std::size_t
>(here - begin) - 1};
504 return std::string_view{begin, len};
512 template<
typename TYPE>
513 inline void into_string(TYPE
const &value, std::string &out);
517 template<
typename TYPE>
518 [[nodiscard]]
inline constexpr
bool is_null(TYPE
const &value) noexcept
528 template<
typename... TYPE>
529 [[nodiscard]]
inline std::size_t
size_buffer(TYPE
const &...value) noexcept
589 template<
typename TYPE>
598 return {begin, traits::into_buf(begin, end, value) - begin - 1};
602 #if defined(PQXX_HAVE_CONCEPTS)
611 concept binary = std::ranges::contiguous_range<TYPE> and
612 std::is_same_v<strip_t<value_type<TYPE>>, std::byte>;
618 #include "pqxx/internal/conversions.hxx"
static TYPE from_string(std::string_view text)
Parse a string representation of a TYPE value.
Definition: strconv.cxx:740
static char * into_buf(char *, char *, TYPE const &)
Definition: strconv.hxx:256
Traits class for use in string conversions.
Definition: strconv.hxx:154
static constexpr bool always_null
Are all values of this type null?
Definition: strconv.hxx:133
static constexpr char * into_buf(char *begin, char *end, ENUM const &value)
Definition: strconv.hxx:378
void into_string(TYPE const &value, std::string &out)
Convert a value to a readable string that PostgreSQL will understand.
Internal items for libpqxx' own use. Do not use these yourself.
Definition: composite.hxx:83
constexpr bool is_sql_array
Does this type translate to an SQL array?
Definition: strconv.hxx:542
The home of all libpqxx classes, functions, templates, etc.
Definition: array.hxx:32
static bool is_null(TYPE const &value)
Is value a null?
static constexpr bool converts_from_string
Definition: strconv.hxx:370
constexpr bool is_unquoted_safe
Can we use this type in arrays and composite types without quoting them?
Definition: strconv.hxx:558
constexpr char array_separator
Element separator between SQL array elements of this type.
Definition: strconv.hxx:562
static bool always_null
Is this type always null?
Definition: strconv.hxx:98
std::underlying_type_t< ENUM > impl_type
Definition: strconv.hxx:366
static std::size_t size_buffer(TYPE const &value) noexcept
Estimate how much buffer space is needed to represent value.
Traits describing a type's "null value," if any.
Definition: strconv.hxx:92
static std::size_t size_buffer(ENUM const &value) noexcept
Definition: strconv.hxx:388
Marker-type wrapper: zero-terminated std::string_view.
Definition: zview.hxx:37
static constexpr zview to_buf(char *begin, char *end, ENUM const &value)
Definition: strconv.hxx:373
std::string const type_name
A human-readable name for a type, used in error messages and such.
Definition: strconv.hxx:82
std::remove_cv_t< std::remove_reference_t< TYPE >> strip_t
Remove any constness, volatile, and reference-ness from a type.
Definition: types.hxx:91
zview generic_to_buf(char *begin, char *end, TYPE const &value)
Implement string_traits::to_buf by calling into_buf.
Definition: strconv.hxx:590
T from_string(field const &value)
Convert a field's value to type T.
Definition: field.hxx:520
static constexpr bool is_null(TYPE const &) noexcept
Does a given value correspond to an SQL null value?
Definition: strconv.hxx:140
static constexpr bool converts_from_string
Is conversion from string_view to TYPE supported?
Definition: strconv.hxx:166
static ENUM from_string(std::string_view text)
Definition: strconv.hxx:383
static char * into_buf(char *begin, char *end, TYPE const &value)
Write value's string representation into buffer at begin.
static std::size_t size_buffer(TYPE const &) noexcept
Definition: strconv.hxx:264
String traits for a forbidden type conversion.
Definition: strconv.hxx:248
constexpr format param_format(TYPE const &)
What's the preferred format for passing non-null parameters of this type?
Definition: strconv.hxx:573
std::string demangle_type_name(char const [])
Attempt to demangle std::type_info::name() to something human-readable.
Definition: strconv.cxx:230
static bool has_null
Does this type have a null value?
Definition: strconv.hxx:95
static TYPE from_string(std::string_view)
Definition: strconv.hxx:260
format
Format code: is data text or binary?
Definition: types.hxx:80
Helper class for defining enum conversions.
Definition: strconv.hxx:364
static TYPE null()
Return a null value.
static constexpr bool converts_to_string
Is conversion from TYPE to strings supported?
Definition: strconv.hxx:160
std::vector< std::string_view > to_buf(char *here, char const *end, TYPE...value)
Convert multiple values to strings inside a single buffer.
Definition: strconv.hxx:497
static constexpr bool has_null
Does TYPE have a "built-in null value"?
Definition: strconv.hxx:127
std::size_t size_buffer(TYPE const &...value) noexcept
Estimate how much buffer space is needed to represent values as a string.
Definition: strconv.hxx:529
std::string to_string(field const &value)
Convert a field to a string.
Definition: result.cxx:549
constexpr bool is_null(TYPE const &value) noexcept
Is value null?
Definition: strconv.hxx:518
void oops_forbidden_conversion() noexcept
Nonexistent function to indicate a disallowed type conversion.
static zview to_buf(char *, char *, TYPE const &)
Definition: strconv.hxx:252
static zview to_buf(char *begin, char *end, TYPE const &value)
Return a string_view representing value, plus terminating zero.
static constexpr bool converts_to_string
Definition: strconv.hxx:369
Nullness traits describing a type which does not have a null value.
Definition: strconv.hxx:114