SysTime.roll

Adds the given number of units to this SysTime. A negative number will subtract.

The difference between rolling and adding is that rolling does not affect larger units. For instance, rolling a SysTime one year's worth of days gets the exact same SysTime.

Accepted units are "days", "minutes", "hours", "minutes", "seconds", "msecs", "usecs", and "hnsecs".

Note that when rolling msecs, usecs or hnsecs, they all add up to a second. So, for example, rolling 1000 msecs is exactly the same as rolling 100,000 usecs.

SysTime roll(long value, AllowDayOverflow allowOverflow)
SysTime roll(long value)
struct SysTime
ref @safe nothrow scope
SysTime
roll
(
string units
)
(
long value
)
if (
units == "days"
)

Parameters

units: The units to add.
value long: The number of units to add to this SysTime.

Examples

import core.time : msecs, hnsecs;
import std.datetime.date : DateTime;

auto st1 = SysTime(DateTime(2010, 1, 1, 11, 23, 12));
st1.roll!"days"(1);
assert(st1 == SysTime(DateTime(2010, 1, 2, 11, 23, 12)));
st1.roll!"days"(365);
assert(st1 == SysTime(DateTime(2010, 1, 26, 11, 23, 12)));
st1.roll!"days"(-32);
assert(st1 == SysTime(DateTime(2010, 1, 25, 11, 23, 12)));

auto st2 = SysTime(DateTime(2010, 7, 4, 12, 0, 0));
st2.roll!"hours"(1);
assert(st2 == SysTime(DateTime(2010, 7, 4, 13, 0, 0)));

auto st3 = SysTime(DateTime(2010, 2, 12, 12, 0, 0));
st3.roll!"hours"(-1);
assert(st3 == SysTime(DateTime(2010, 2, 12, 11, 0, 0)));

auto st4 = SysTime(DateTime(2009, 12, 31, 0, 0, 0));
st4.roll!"minutes"(1);
assert(st4 == SysTime(DateTime(2009, 12, 31, 0, 1, 0)));

auto st5 = SysTime(DateTime(2010, 1, 1, 0, 0, 0));
st5.roll!"minutes"(-1);
assert(st5 == SysTime(DateTime(2010, 1, 1, 0, 59, 0)));

auto st6 = SysTime(DateTime(2009, 12, 31, 0, 0, 0));
st6.roll!"seconds"(1);
assert(st6 == SysTime(DateTime(2009, 12, 31, 0, 0, 1)));

auto st7 = SysTime(DateTime(2010, 1, 1, 0, 0, 0));
st7.roll!"seconds"(-1);
assert(st7 == SysTime(DateTime(2010, 1, 1, 0, 0, 59)));

auto dt = DateTime(2010, 1, 1, 0, 0, 0);
auto st8 = SysTime(dt);
st8.roll!"msecs"(1);
assert(st8 == SysTime(dt, msecs(1)));

auto st9 = SysTime(dt);
st9.roll!"msecs"(-1);
assert(st9 == SysTime(dt, msecs(999)));

auto st10 = SysTime(dt);
st10.roll!"hnsecs"(1);
assert(st10 == SysTime(dt, hnsecs(1)));

auto st11 = SysTime(dt);
st11.roll!"hnsecs"(-1);
assert(st11 == SysTime(dt, hnsecs(9_999_999)));

SysTime.roll

Parameters

Examples

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