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`std.datetime.date.Date.roll` - multiple declarations

Function Date.roll

Adds the given number of years or months to this Date. A negative number will subtract.


						
				ref Date roll(string units)
				(
				

				  long value,
				

				  AllowDayOverflow allowOverflow = AllowDayOverflow.yes
				

				) pure nothrow @nogc @safe
				

				if (units == "years");

The difference between rolling and adding is that rolling does not affect larger units. Rolling a Date 12 months gets the exact same Date. However, the days can still be affected due to the differing number of days in each month.

Because there are no units larger than years, there is no difference between adding and rolling years.

Parameters

Name	Description
units	The type of units to add ("years" or "months").
value	The number of months or years to add to this `Date`.
allowOverflow	Whether the day should be allowed to overflow, causing the month to increment.

Example

auto d1 = Date(2010, 1, 1);
d1.roll!"months"(1);
writeln(d1); // Date(2010, 2, 1)

auto d2 = Date(2010, 1, 1);
d2.roll!"months"(-1);
writeln(d2); // Date(2010, 12, 1)

auto d3 = Date(1999, 1, 29);
d3.roll!"months"(1);
writeln(d3); // Date(1999, 3, 1)

auto d4 = Date(1999, 1, 29);
d4.roll!"months"(1, AllowDayOverflow.no);
writeln(d4); // Date(1999, 2, 28)

auto d5 = Date(2000, 2, 29);
d5.roll!"years"(1);
writeln(d5); // Date(2001, 3, 1)

auto d6 = Date(2000, 2, 29);
d6.roll!"years"(1, AllowDayOverflow.no);
writeln(d6); // Date(2001, 2, 28)

Function Date.roll

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


						
				ref Date roll(string units)
				(
				

				  long days
				

				) pure nothrow @nogc @safe
				

				if (units == "days");

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

The only accepted units are "days".

Parameters

Name	Description
units	The units to add. Must be `"days"`.
days	The number of days to add to this `Date`.

Example

auto d = Date(2010, 1, 1);
d.roll!"days"(1);
writeln(d); // Date(2010, 1, 2)
d.roll!"days"(365);
writeln(d); // Date(2010, 1, 26)
d.roll!"days"(-32);
writeln(d); // Date(2010, 1, 25)

Authors

Jonathan M Davis

License

Boost License 1.0.

API Documentation

std.datetime.date.Date.roll - multiple declarations

Function Date.roll

Parameters

Example

Function Date.roll

Parameters

Example

Authors

License

`std.datetime.date.Date.roll` - multiple declarations