From type/Dateish

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multi method earlier(Dateish:D: *%unit)
multi method earlier(Dateish:D: @pairs)

Returns an object based on the current one, but with a date delta towards the past applied. Unless the given unit is second or seconds, the given value will be converted to an Int. See .later for usage. It will generally be used through classes that implement this role, Date or DateTime

my $d = Date.new('2015-02-27');
say $d.earlier(month => 5).earlier(:2days);  # OUTPUT: «2014-09-25␤» 
my $d = DateTime.new(date => Date.new('2015-02-27'));
say $d.earlier(month => 1).earlier(:2days);  # OUTPUT: «2015-01-25T00:00:00Z␤»

If the resultant time has value 60 for seconds, yet no leap second actually exists for that time, seconds will be set to 59:

say DateTime.new('2008-12-31T23:59:60Z').earlier: :1day;
# OUTPUT: «2008-12-30T23:59:59Z␤»

Negative offsets are allowed, though later is more idiomatic for that.

If you need to use more than one unit, you will need to build them into a List of Pairs to use the second form of the method:

say Date.new('2021-03-31').earlier(  ( year => 3, month => 2, day => 8 ) ); # OUTPUT: «2018-01-23␤» 

This feature was introduced in release 2021.02 of the Rakudo compiler.