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perl/Examples/Chap3/chrono-3

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+
+
+###
+### chronologically-3
+###
+
+## Chapter 3 section 10
+
+@sorted_dates = sort chronologically @dates;
+
+%m2n = 
+   ( jan =>  1, feb =>  2, mar =>  3,
+     apr =>  4, may =>  5, jun =>  6, 
+     jul =>  7, aug =>  8, sep =>  9, 
+     oct => 10, nov => 11, dec => 12, );
+
+sub chronologically {
+  date_to_string($a) cmp date_to_string($b)
+}
+
+sub date_to_string {
+  my ($m, $d, $y) = ($_[0] =~ /(\w{3}) (\d+), (\d+)/);
+  sprintf "%04d%02d%02d", $y, $m2n{lc $m}, $d;
+}