fig08_06.pl

PERL语言资料 可以用于PERL程序设计

#!usr/bin/perl
# Fig 8.6: fig08_06.pl
# Showing the dangers of using alternate without parentheses.

use strict;
use warnings;

my $string1 = "hello";
my $string2 = "hello there";
my $string3 = "hi there";

print "$string1\n$string2\n$string3\n";

print "watch this:\n";

print "1: how are you?\n" if ( $string1 =~ m/hello|hi there/ );
print "2: how are you?\n" if ( $string2 =~ m/hello|hi there/ );
print "3: how are you?\n" if ( $string3 =~ m/hello|hi there/ );

print "now watch this:\n";

print "1: how are you?\n" 
   if ( $string1 =~ m/(hello|hi) there/ );
print "2: how are you?\n" 
   if ( $string2 =~ m/(hello|hi) there/ );
print "3: how are you?\n" 
   if ( $string3 =~ m/(hello|hi) there/ );

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