Array elements existence check: 
my @all  = 1..10;
my @some = 1..5;
my %h;
my @c;

@h{@some} = ( );

# Elements that exist in both arrays
exists($h{$_}) and push @c, $_ for @all;
# @c: 1 2 3 4 5

# Elements that do not exist in @some array
exists($h{$_}) or push @c, $_ for @all;
# @c: 6 7 8 9 10

[download]
Pattern matching negation: 
my $string = 'string';

# true:
$string =~ /^string$/ and print "$string is really string?\n";
# false:
$string !~ /^string$/ and print "$string is not string?\n";
# STDOUT: string is really string

[download]


In reply to Re: To Pattern Match or not to Pattern Match by sh1tn
in thread To Pattern Match or not to Pattern Match by Anonymous Monk

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