Your leap year calculation is incorrect. 2004 is a leap year, 2000 is a leap year, 1904 is a leap year, but 1900 is NOT. The rule is: 
if (!($y % 4) and ($y % 100 or !($y % 400))) { ... }

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Other than that, here's a much simpler method for finding out yesterday: 
use Time::Local;

my $noon = timelocal(0,0,12, (localtime)[3,4,5]);
my ($d,$m,$y) = (localtime($noon - 86400))[3,4,5];

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_____________________________________________________
Jeff[japhy]Pinyan: Perl, regex, and perl hacker.
s++=END;++y(;-P)}y js++=;shajsj<++y(p-q)}?print:??;

In reply to Re: Module Code Review by japhy
in thread Module Code Review by TStanley

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