If you disregard timezones, my favourite method of calculating yesterday's date is the following:

my $yesterday = localtime;
sleep( 86400 );
print "Yesterdays date is $yesterday\n";

[download]

People might complain that the runtime is a bit too long, but I'm sure one can reduce the runtime by rewriting this program in C, Haskell or Perl6.

In reply to Re^2: Date Manipulation by Corion
in thread Date Manipulation by SR

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