Appendix A. Answers to ExercisesContents:
Answers for Chapter 2 This appendix contains the answers to the exercises presented throughout the book. A.1. Answers for Chapter 2A.1.1. Exercise 1 (Section 2.10.1)Here's one way to do it. First, start with the package directive and use strict: package Oogaboogoo::date; use strict; Then define the constant arrays to hold the mappings for day-of-week and month names: my @day = qw(ark dip wap sen pop sep kir); my @mon = qw(diz pod bod rod sip wax lin sen kun fiz nap dep); Next, define the subroutine for day-of-week-number to name. Note that this subroutine will be accessible as Ooogaboogoo::date::day: sub day { my $num = shift @_; die "$num is not a valid day number" unless $num >= 0 and $num <= 6; $day[$num]; } Similarly, you have the subroutine for the month-of-year-number to name: sub mon { my $num = shift @_; die "$num is not a valid month number" unless $num >= 0 and $num <= 11; $mon[$num]; } Finally, the mandatory true value at the end of the package: 1; Name this file date.pl within a directory of Oogaboogoo in one of the directories given in your @INC variable, such as the current directory. A.1.2. Exercise 2 (Section 2.10.2)Here's one way to do it. Pull in the .pl file from a place in your @INC path: use strict; require 'Oogaboogoo/date.pl'; Then get the information for the current time: my($sec, $min, $hour, $mday, $mon, $year, $wday) = localtime; Then use the newly defined subroutines for the conversions: my $day_name = Oogaboogoo::date::day($wday); my $mon_name = Oogaboogoo::date::mon($mon); The year number is offset by 1900 for historical purposes, so you need to fix that: $year += 1900; Finally, it's time for the output: print "Today is $day_name, $mon_name $mday, $year.\n"; Copyright © 2003 O'Reilly & Associates. All rights reserved. |
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