Date Range

$ perl6 -e '.say for Date.today.truncated-to("month") ... Date.today'
2019-10-01
2019-10-02
2019-10-03
2019-10-04
2019-10-05
2019-10-06
2019-10-07
2019-10-08

OR

use Date::Simple qw/date today/;

my $d1 = date('2019-10-01');
my $d2 = today;

say for map $d1 + $_, 0 .. $d2 - $d1;

OR

perl -MTime::Seconds -MTime::Piece -E '
    my $end = localtime; 
    my $start = Time::Piece->strptime( 
        $end->strftime("%Y-%m-01"), "%Y-%m-%d"); 
    while ( $start->epoch <= $end->epoch ) { 
        say $start->ymd; 
        $start += ONE_DAY;
    }
'