morph::time::DateTime Struct Reference

A UTC instant with millisecond precision. More...

#include <datetime.hpp>

Public Member Functions
constexpr	DateTime () noexcept=default
	Constructs the Unix epoch (1970-01-01T00:00:00.000Z).
constexpr	DateTime (std::chrono::sys_time< std::chrono::milliseconds > instant) noexcept
	Wraps an existing UTC instant.
constexpr	DateTime (std::chrono::year year, std::chrono::month month, std::chrono::day day, std::chrono::hours hour, std::chrono::minutes minute, std::chrono::seconds second, std::chrono::milliseconds millisecond=std::chrono::milliseconds{0}) noexcept
	Composes a UTC instant from calendar/clock components.
std::string	toIso8601 () const
	Renders as ISO-8601 UTC: YYYY-MM-DDTHH:MM:SS.mmmZ.
constexpr std::strong_ordering	operator<=> (const DateTime &other) const noexcept=default
	Ordering on the underlying instant.
template<typename Rep, typename Period>
constexpr DateTime &	operator+= (std::chrono::duration< Rep, Period > delta) noexcept
	Shifts this instant by an arbitrary chrono duration.
template<typename Rep, typename Period>
constexpr DateTime &	operator-= (std::chrono::duration< Rep, Period > delta) noexcept
	Shifts this instant backwards by an arbitrary chrono duration.

Static Public Member Functions
static DateTime	now () noexcept
	The current UTC instant, truncated to milliseconds.
static std::optional< DateTime >	fromIso8601 (std::string_view text) noexcept
	Strictly parses ISO-8601 UTC: YYYY-MM-DDTHH:MM:SS, optionally followed by .m/.mm/.mmm and an optional trailing Z.

Public Attributes
std::chrono::sys_time< std::chrono::milliseconds >	value
	The underlying UTC instant (Unix time, leap seconds ignored).

Detailed Description

A UTC instant with millisecond precision.

The default state is the Unix epoch — DateTime itself has no empty state; use Timestamp for fields that may be blank.

Definition at line 71 of file datetime.hpp.

Constructor & Destructor Documentation

DateTime() [1/2]

morph::time::DateTime::DateTime ( std::chrono::sys_time< std::chrono::milliseconds > instant )

inlineconstexprnoexcept

Wraps an existing UTC instant.

Parameters

instant

The UTC instant to wrap.

Definition at line 80 of file datetime.hpp.

DateTime() [2/2]

morph::time::DateTime::DateTime ( std::chrono::year year, std::chrono::month month, std::chrono::day day, std::chrono::hours hour, std::chrono::minutes minute, std::chrono::seconds second, std::chrono::milliseconds millisecond = std::chrono::milliseconds{0} )

inlineconstexprnoexcept

Composes a UTC instant from calendar/clock components.

Parameters

year	Calendar year.
month	Month-of-year in [1, 12].
day	Day-of-month in [1, 31].
hour	Hours in [0, 23].
minute	Minutes in [0, 59].
second	Seconds in [0, 59].
millisecond	Milliseconds in [0, 999].

Definition at line 90 of file datetime.hpp.

Member Function Documentation

now()

DateTime morph::time::DateTime::now ( )

inlinestaticnodiscardnoexcept

The current UTC instant, truncated to milliseconds.

Consults the process-wide clock override installed via setNowOverride/ ScopedNowOverride, if any; otherwise calls std::chrono::system_clock::now() directly. This is the seam that lets registry-constructed (remotely instantiated) models get a deterministic "now" in tests without any constructor parameter: production code calls DateTime::now() exactly as before, and a test installs an override for its scope. See ScopedNowOverride.

Warning

This function is noexcept. If an installed override callable throws, that exception escapes a noexcept function and std::terminate() is called — an override must not throw. The override also runs while the internal mutex is held, so it must not itself call DateTime::now() / Timestamp::now(), setNowOverride, or construct a ScopedNowOverride: the mutex is non-recursive and any of those would self-deadlock (the same constraint morph::log's sink callback documents for the same reason).

Returns

The current UTC date-time, or the overridden instant if one is installed.

Definition at line 114 of file datetime.hpp.

toIso8601()

std::string morph::time::DateTime::toIso8601 ( ) const

inlinenodiscard

Renders as ISO-8601 UTC: YYYY-MM-DDTHH:MM:SS.mmmZ.

Returns

The formatted instant.

Definition at line 127 of file datetime.hpp.

fromIso8601()

std::optional< DateTime > morph::time::DateTime::fromIso8601 ( std::string_view text )

inlinestaticnodiscardnoexcept

Strictly parses ISO-8601 UTC: YYYY-MM-DDTHH:MM:SS, optionally followed by .m/.mm/.mmm and an optional trailing Z.

The calendar date must exist (2026-02-30 is rejected) and clock components must be in range; no time zones other than Z, no lowercase separators, no trailing input. The fixed-width date and clock fields (month, day, hour, minute, second, fraction) reject a leading sign; only the year field may carry a - (negative years).

Parameters

text	Candidate ISO-8601 string.

Returns

The parsed instant, or std::nullopt when text is malformed.

Definition at line 148 of file datetime.hpp.

operator<=>()

std::strong_ordering morph::time::DateTime::operator<=> ( const DateTime & other ) const

nodiscardconstexprdefaultnoexcept

Ordering on the underlying instant.

Parameters

other

Instant to compare against.

Returns

The relative ordering of the two instants.

operator+=()

template<typename Rep, typename Period>

DateTime & morph::time::DateTime::operator+= ( std::chrono::duration< Rep, Period > delta )

inlineconstexprnoexcept

Shifts this instant by an arbitrary chrono duration.

Parameters

delta

Duration to add (may be negative).

Returns

*this.

Definition at line 238 of file datetime.hpp.

operator-=()

template<typename Rep, typename Period>

DateTime & morph::time::DateTime::operator-= ( std::chrono::duration< Rep, Period > delta )

inlineconstexprnoexcept

Shifts this instant backwards by an arbitrary chrono duration.

Parameters

delta

Duration to subtract (may be negative).

Returns

*this.

Definition at line 247 of file datetime.hpp.

Member Data Documentation

value

std::chrono::sys_time<std::chrono::milliseconds> morph::time::DateTime::value

The underlying UTC instant (Unix time, leap seconds ignored).

Definition at line 73 of file datetime.hpp.

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The documentation for this struct was generated from the following file:

• morph/util/datetime.hpp