google::cloud::spanner::Decimal< DecimalMode > Class Template Reference

A representation of the Spanner NUMERIC type: an exact decimal value with a maximum integer precision (kIntPrecision) and rounding to a maximum fractional precision (kFracPrecision). More...

#include <google/cloud/spanner/numeric.h>

Public Member Functions
	Decimal ()
	A zero value. More...
Regular value type, supporting copy, assign, move.
	Decimal (Decimal &&) noexcept=default
Decimal &	operator= (Decimal &&) noexcept=default
	Decimal (Decimal const &)=default
Decimal &	operator= (Decimal const &)=default
std::string const &	ToString () const &
	Conversion to a decimal-string representation of the Decimal in one of the following forms: More...
std::string &&	ToString () &&
	Conversion to a decimal-string representation of the Decimal in one of the following forms: More...

Static Public Attributes
static bool const	kHasNaN
	Whether DecimalMode supports NaN values. More...
Integer and fractional precision of a <tt>Decimal</tt> value of the mode.
static std::size_t const	kIntPrecision
static std::size_t const	kFracPrecision
Backwards-compatibility constants.
Deprecated: Only apply to kGoogleSQL mode, and are no longer used in the implementation.
static constexpr std::size_t	kIntPrec = 29
static constexpr std::size_t	kFracPrec = 9

Friends
std::ostream &	operator<< (std::ostream &os, Decimal const &d)
	Outputs string representation of the Decimal to the provided stream. More...
Relational operators
bool	operator== (Decimal const &a, Decimal const &b)
bool	operator!= (Decimal const &a, Decimal const &b)

Detailed Description

template<DecimalMode>
class google::cloud::spanner::Decimal< DecimalMode >

A representation of the Spanner NUMERIC type: an exact decimal value with a maximum integer precision (kIntPrecision) and rounding to a maximum fractional precision (kFracPrecision).

A Decimal can be constructed from, and converted to a std::string, a double, or any integral type. See the MakeDecimal() factory functions, the ToString() member function, and the ToDouble()/ToInteger() free functions.

Decimal values can be copied/assigned/moved, compared for equality, and streamed.

Example

auto d = spanner::MakeDecimal<spanner::DecimalMode::kGoogleSQL>(42).value();
assert(d.ToString() == "42");
assert(spanner::ToInteger<int>(d).value() == 42);

Constructor & Destructor Documentation

Decimal() [1/3]

template<DecimalMode >

google::cloud::spanner::Decimal< DecimalMode >::Decimal ( )

inline

A zero value.

Decimal() [2/3]

template<DecimalMode >

google::cloud::spanner::Decimal< DecimalMode >::Decimal ( Decimal< DecimalMode > &&  )

defaultnoexcept

Decimal() [3/3]

template<DecimalMode >

google::cloud::spanner::Decimal< DecimalMode >::Decimal ( Decimal< DecimalMode > const &  )

default

Member Function Documentation

operator=() [1/2]

template<DecimalMode >

Decimal & google::cloud::spanner::Decimal< DecimalMode >::operator= ( Decimal< DecimalMode > &&  )

defaultnoexcept

operator=() [2/2]

template<DecimalMode >

Decimal & google::cloud::spanner::Decimal< DecimalMode >::operator= ( Decimal< DecimalMode > const &  )

default

ToString() [1/2]

template<DecimalMode >

std::string && google::cloud::spanner::Decimal< DecimalMode >::ToString ( ) &&

inline

Conversion to a decimal-string representation of the Decimal in one of the following forms:

• 0 // value == 0
• -?0.[0-9]*[1-9] // 0 < abs(value) < 1
• -?[1-9][0-9]*(.[0-9]*[1-9])? // abs(value) >= 1
• NaN // "not a number" for kPostgreSQL mode

Note: The string never includes an exponent field.

ToString() [2/2]

template<DecimalMode >

std::string const & google::cloud::spanner::Decimal< DecimalMode >::ToString ( ) const &

inline

Conversion to a decimal-string representation of the Decimal in one of the following forms:

• 0 // value == 0
• -?0.[0-9]*[1-9] // 0 < abs(value) < 1
• -?[1-9][0-9]*(.[0-9]*[1-9])? // abs(value) >= 1
• NaN // "not a number" for kPostgreSQL mode

Note: The string never includes an exponent field.

Friends And Related Function Documentation

operator!=

template<DecimalMode >

bool operator!= ( Decimal< DecimalMode > const &  a, Decimal< DecimalMode > const &  b  )

friend

operator<<

template<DecimalMode >

std::ostream & operator<< ( std::ostream &  os, Decimal< DecimalMode > const &  d  )

friend

Outputs string representation of the Decimal to the provided stream.

operator==

template<DecimalMode >

bool operator== ( Decimal< DecimalMode > const &  a, Decimal< DecimalMode > const &  b  )

friend

Member Data Documentation

kFracPrec

template<DecimalMode Mode>

constexpr std::size_t google::cloud::spanner::Decimal< Mode >::kFracPrec = 9

staticconstexpr

kFracPrecision

template<DecimalMode >

std::size_t const google::cloud::spanner::Decimal< DecimalMode >::kFracPrecision

static

kHasNaN

template<DecimalMode >

bool const google::cloud::spanner::Decimal< DecimalMode >::kHasNaN

static

Whether DecimalMode supports NaN values.

kIntPrec

template<DecimalMode Mode>

constexpr std::size_t google::cloud::spanner::Decimal< Mode >::kIntPrec = 29

staticconstexpr

kIntPrecision

template<DecimalMode >

std::size_t const google::cloud::spanner::Decimal< DecimalMode >::kIntPrecision

static