use warnings;
use strict;
use Date::Calc qw/Add_Delta_YM/;

sub prevmonth {
    my ($year, $month) = @_;
    my ($newyear, $newmonth, undef)
        = Add_Delta_YM( $year, $month, 1, 0, -1 );
    return [$newyear, $newmonth];
}

use Test::More;

is_deeply prevmonth(2003,8), [2003,7];
is_deeply prevmonth(2004,1), [2003,12];

done_testing;

[download]

Update: This is also possible with the core module Time::Piece. If you have a modern browser like the latest Firefox or Chrome, here is a live demo of the following code.

use warnings;
use strict;
use Time::Piece;

while (<>) {
    chomp;
    my $t = Time::Piece->strptime($_, '%m/%Y');
    my $prev = $t->add_months(-1);
    print $prev->strftime('%m/%Y'), "\n";
}

[download]

In reply to Re: How to get last month date using Date::Calc by haukex
in thread How to get last month date using Date::Calc by kanewilliam7777

Title:
Use:  <p> text here (a paragraph) </p>
and:  <code> code here </code>
to format your post, it's "PerlMonks-approved HTML":


  • Posts are HTML formatted. Put <p> </p> tags around your paragraphs. Put <code> </code> tags around your code and data!
  • Titles consisting of a single word are discouraged, and in most cases are disallowed outright.
  • Read Where should I post X? if you're not absolutely sure you're posting in the right place.
  • Please read these before you post! —
  • Posts may use any of the Perl Monks Approved HTML tags:
    a, abbr, b, big, blockquote, br, caption, center, col, colgroup, dd, del, details, div, dl, dt, em, font, h1, h2, h3, h4, h5, h6, hr, i, ins, li, ol, p, pre, readmore, small, span, spoiler, strike, strong, sub, summary, sup, table, tbody, td, tfoot, th, thead, tr, tt, u, ul, wbr
  • You may need to use entities for some characters, as follows. (Exception: Within code tags, you can put the characters literally.)
            For:     Use:
    & &amp;
    < &lt;
    > &gt;
    [ &#91;
    ] &#93;
  • Link using PerlMonks shortcuts! What shortcuts can I use for linking?
  • See Writeup Formatting Tips and other pages linked from there for more info.