asap::datetime Class Reference

The asap::datetime class exposes methods to create, manipulate and print dates. More...

Public Member Functions
	datetime (time_t time=std::time(nullptr)) noexcept
	Constructs a asap::datetime from a time_t, defaulting to the current time. More...
	datetime (const std::string &datetime, const std::string &format="%x %X", const std::string &locale="")
	Constructs a asap::datetime from a string, optionally with a format and a locale. More...
	datetime (uint32_t year, uint32_t month, uint32_t day, uint32_t hours=0, uint32_t minutes=0, uint32_t seconds=0)
	Constructs a asap::datetime from a broken down time. More...
datetime &	operator+= (const seconds &d)
	Adds a duration specified in seconds to a datetime. More...
datetime &	operator+= (const minutes &d)
	Adds a duration specified in minutes to a datetime. More...
datetime &	operator+= (const hours &d)
	Adds a duration specified in hours to a datetime. More...
datetime &	operator+= (const days &d)
	Adds a duration specified in days to a datetime. More...
datetime &	operator+= (const weeks &d)
	Adds a duration specified in weeks to a datetime. More...
datetime &	operator+= (const months &d)
	Adds a duration specified in months to a datetime. More...
datetime &	operator+= (const years &d)
	Adds a duration specified in years to a datetime. More...
asap::seconds	operator- (const datetime &other) const
	Returns a duration in seconds specifying the difference to another datetime. More...
template<uint64_t convert>
asap::datetime &	operator-= (const asap::duration< convert > &c)
	Subtracts a duration from this datetime. More...
asap::datetime &	operator+= (time_t stamp)
	Adds a duration specified in seconds since epoch to a datetime. More...
asap::datetime &	operator-= (time_t stamp)
	Subtracts a duration specified in seconds since epoch from a datetime. More...
asap::datetime	morning ()
	Creates a new asap::datetime representing the morning of the same day. More...
asap::datetime	afternoon ()
	Creates a new asap::datetime representing the afternoon of the same day. More...
asap::datetime	midnight ()
	Creates a new asap::datetime representing the midnight of the same day. More...
time_t	timestamp () const
	Converts an asap::datetime to a time_t More...
std::string	str (const std::string &fmt="%x %X") const
	Converts to an string using the format specified. More...
asap::period	until (const asap::datetime &dt) const
	Creates an instance of asap::period starting at this datetime and ending at dt. More...
int	second () const
	Returns the seconds of a minute specified in this asap::datetime. More...
asap::datetime &	second (int value)
	Sets the seconds in a minute specified in this asap::datetime. More...
int	minute () const
	Returns the minutes of an hour specified in this asap::datetime. More...
asap::datetime &	minute (int value)
	Sets the minutes in an hour specified in this asap::datetime. More...
int	hour () const
	Returns the hours of a day specified in this asap::datetime. More...
asap::datetime &	hour (int value)
	Sets the hour of a day specified in this asap::datetime. More...
int	wday () const
	Returns the day of a week specified in this asap::datetime. More...
asap::datetime &	wday (int value)
	Sets the day of a week specified in this asap::datetime (0-6) More...
int	mday () const
	Returns the day of a month specified in this asap::datetime. More...
asap::datetime &	mday (int value)
	Sets the day of a month specified in this asap::datetime (1-31) More...
int	yday () const
	Returns the day in a year specified in this asap::datetime. More...
asap::datetime &	yday (int value)
	Sets the day in a year specified in this asap::datetime (1-365) More...
int	month () const
	Returns the month in a year specified in this asap::datetime. More...
asap::datetime &	month (int value)
	Sets the month in a year specified in this asap::datetime (0-11) More...
int	year () const
	Returns the year specified in this asap::datetime. More...
asap::datetime &	year (int value)
	Sets the year specified in this asap::duration. More...

Detailed Description

The asap::datetime class exposes methods to create, manipulate and print dates.

It can be constructed from:

• another asap::datetime
• a string in a known format
• a string with a specified format
• seconds from unix epoch
• broken-down time (ie., asap::datetime(2007, 6, 1, 0, 0, 0)) for July 1 2007

asap::datetime has overloads for printing to an std::iostream so you can directly print to std::cout:

std::cout << asap::now() << std::endl;

You can also format it via the asap::datetime::str method

std::cout << asap::now().str("%c") << std::endl;

Definition at line 29 of file datetime.h.

Constructor & Destructor Documentation

datetime() [1/3]

asap::datetime::datetime ( time_t  time = std::time(nullptr) )

explicitnoexcept

Constructs a asap::datetime from a time_t, defaulting to the current time.

Parameters

time	The time specified as seconds since epoch (time_t)

This is also the default asap::datetime constructor

datetime() [2/3]

asap::datetime::datetime ( const std::string &  datetime, const std::string &  format = "%x %X", const std::string &  locale = ""  )

explicit

Constructs a asap::datetime from a string, optionally with a format and a locale.

Parameters

datetime	The datetime specified in a string
format	The datetime format, defaults to "%x %X" which is equivalent to "%d/%m/%Y %H:%M:%S" on some locales and "m/d/Y H:M:S in en_US locale)
locale	The locale to specify when reading the string

This constructor tries its best to read the date and time specified in the string. This is what it tries:

• Read the string in the specified format and locale
• Convert the datetime back to a string using the same format and locale
• If the strings are equal, it stops
• If not it tries the next known format
• If nothing works, defaults to 0 seconds since epoch.

One can argue this is the slowest method in the library.

datetime() [3/3]

asap::datetime::datetime	(	uint32_t	year,
		uint32_t	month,
		uint32_t	day,
		uint32_t	hours = 0,
		uint32_t	minutes = 0,
		uint32_t	seconds = 0
	)

Constructs a asap::datetime from a broken down time.

Parameters

year	The year
month	The 0-based month (e.g, 0 for January)
day	The day of the month (not the day of the year!)
hours	Hour of the day
minutes	Minutes of the day
seconds	Seconds of the day

Member Function Documentation

afternoon()

asap::datetime::afternoon

(

)

Creates a new asap::datetime representing the afternoon of the same day.

Returns

a new asap::datetime at 12 pm in the same day (which usually is considered afternoon around the world)

hour() [1/2]

asap::datetime::hour

(

)

const

Returns the hours of a day specified in this asap::datetime.

Returns

hours of a day of this asap::datetime

hour() [2/2]

asap::datetime::hour

(

int

value

)

Sets the hour of a day specified in this asap::datetime.

Parameters

value

The value to set

Returns

*this

You can overflow this value and it will be converted correctly

mday() [1/2]

asap::datetime::mday

(

)

const

Returns the day of a month specified in this asap::datetime.

Returns

day of a month of this asap::datetime

mday() [2/2]

asap::datetime::mday

(

int

value

)

Sets the day of a month specified in this asap::datetime (1-31)

Parameters

value

The value to set

Returns

*this

You can overflow this value and it will be converted correctly

midnight()

asap::datetime::midnight

(

)

Creates a new asap::datetime representing the midnight of the same day.

Returns

a new asap::datetime at 0 am in the same day

minute() [1/2]

asap::datetime::minute

(

)

const

Returns the minutes of an hour specified in this asap::datetime.

Returns

minutes of an hour

minute() [2/2]

asap::datetime::minute

(

int

value

)

Sets the minutes in an hour specified in this asap::datetime.

Parameters

value

The value to set

Returns

*this

You can overflow this value and it will be converted correctly

month() [1/2]

asap::datetime::month

(

)

const

Returns the month in a year specified in this asap::datetime.

Returns

month in a year

month() [2/2]

asap::datetime::month

(

int

value

)

Sets the month in a year specified in this asap::datetime (0-11)

Parameters

value

The value to set

Returns

*this

You can overflow this value and it will be converted correctly

morning()

asap::datetime::morning

(

)

Creates a new asap::datetime representing the morning of the same day.

Returns

a new asap::datetime at 6 am in the same day (which usually is considered morning around the world)

operator+=() [1/8]

asap::datetime::operator+=

(

const seconds &

d

)

Adds a duration specified in seconds to a datetime.

Parameters

d	The duration specified in seconds

Returns

*this

operator+=() [2/8]

asap::datetime::operator+=

(

const minutes &

d

)

Adds a duration specified in minutes to a datetime.

Parameters

d	The duration specified in minutes

Returns

*this

operator+=() [3/8]

asap::datetime::operator+=

(

const hours &

d

)

Adds a duration specified in hours to a datetime.

Parameters

d	The duration specified in hours

Returns

*this

operator+=() [4/8]

asap::datetime::operator+=

(

const days &

d

)

Adds a duration specified in days to a datetime.

Parameters

d	The duration specified in days

Returns

*this

operator+=() [5/8]

asap::datetime::operator+=

(

const weeks &

d

)

Adds a duration specified in weeks to a datetime.

Parameters

d	The duration specified in weeks

Returns

*this

operator+=() [6/8]

asap::datetime::operator+=

(

const months &

d

)

Adds a duration specified in months to a datetime.

Parameters

d	The duration specified in months

Returns

*this

operator+=() [7/8]

asap::datetime::operator+=

(

const years &

d

)

Adds a duration specified in years to a datetime.

Parameters

d	The duration specified in years

Returns

*this

operator+=() [8/8]

asap::datetime::operator+=

(

time_t

stamp

)

Adds a duration specified in seconds since epoch to a datetime.

Parameters

stamp

The duration specified in seconds since epoch

Returns

*this

operator-()

asap::datetime::operator-

(

const datetime &

other

)

const

Returns a duration in seconds specifying the difference to another datetime.

Parameters

other

The datetime to calculate the difference

Returns

an instance of asap::seconds representing the difference to other

operator-=() [1/2]

template<uint64_t convert>

asap::datetime::operator-=

(

const asap::duration< convert > &

c

)

Subtracts a duration from this datetime.

Template Parameters

convert

The converting factor for the duration (automatically deduced)

Parameters

c	The duration

Returns

*this

operator-=() [2/2]

asap::datetime::operator-=

(

time_t

stamp

)

Subtracts a duration specified in seconds since epoch from a datetime.

Parameters

stamp

The duration specified in seconds since epoch

Returns

*this

second() [1/2]

asap::datetime::second

(

)

const

Returns the seconds of a minute specified in this asap::datetime.

Returns

seconds of a minute

second() [2/2]

asap::datetime::second

(

int

value

)

Sets the seconds in a minute specified in this asap::datetime.

Parameters

value

The value to set

Returns

*this

You can overflow this value and it will be converted correctly

str()

asap::datetime::str

(

const std::string &

fmt = "%x %X"

)

const

Converts to an string using the format specified.

Parameters

fmt	The format to use when converting

Returns

A std::string with the resulting conversion

timestamp()

asap::datetime::timestamp

(

)

const

Converts an asap::datetime to a time_t

Returns

the timestamp of this asap::datetime in time_t

until()

asap::datetime::until

(

const asap::datetime &

dt

)

const

Creates an instance of asap::period starting at this datetime and ending at dt.

Parameters

dt	Ending datetime

Returns

An instance of asap::period

wday() [1/2]

asap::datetime::wday

(

)

const

Returns the day of a week specified in this asap::datetime.

Returns

day of a week of this asap::datetime

wday() [2/2]

asap::datetime::wday

(

int

value

)

Sets the day of a week specified in this asap::datetime (0-6)

Parameters

value

The value to set

Returns

*this

You can overflow this value and it will be converted correctly

yday() [1/2]

asap::datetime::yday

(

)

const

Returns the day in a year specified in this asap::datetime.

Returns

day in a year

yday() [2/2]

asap::datetime::yday

(

int

value

)

Sets the day in a year specified in this asap::datetime (1-365)

Parameters

value

The value to set

Returns

*this

You can overflow this value and it will be converted correctly

year() [1/2]

asap::datetime::year

(

)

const

Returns the year specified in this asap::datetime.

Returns

year of this asap::datetime

year() [2/2]

asap::datetime::year

(

int

value

)

Sets the year specified in this asap::duration.

Parameters

value

The value to set

Returns

*this