As this is mostly static info (except for leap years), you might just want to use a simple lookup table. 

my %period = (
    Jan => ['01 Dec','31 Dec'],
    Feb => ['01 Jan','31 Jan'],
    Mar => ['01 Feb','28 Feb'],
    #...
    Dec => ['01 Nov','30 Nov'],
);

my $curr_month = "Mar";
my $curr_year  = 2010;

my $p = $period{$curr_month};
print "$p->[0] $curr_year - $p->[1] $curr_year\n";   # 01 Feb 2010 - 2
+8 Feb 2010

[download]

To figure out when the "28 Feb" isn't correct, you could use one of the many date modules on CPAN (this is left as an exercise for... :).  Or simply hardcode a list of those years up until the time you'll retire ;)

Update: the following should also work for up to 2099 

...
my $p = $period{$curr_month};
if ($curr_month eq "Mar") {
    $p->[1] = '29 Feb' unless $curr_year % 4;
}
...

[download]

In reply to Re: How to get last month date period by almut
in thread How to get last month date period by roborat

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