Frequently Used PERL Code

iDog

General

Check if a variable is initialized:

if(defined $myVar) {
    # ...
}

Regex

Validate email address:

if($email =~ /^[^@\t ]+@[^@.\t]+(\.[^@.\n ]+)+$/) {
    # ...
}

System

Get env variable:

my $envValue = "";
$envValue = $ENV{$envKey} if(exists $ENV{envKey});

Check if a module is installed:

perl -MDigest::HMAC_SHA1 -e 1

List all installed modules:

perl -MFile::Find=find -MFile::Spec::Functions -lwe 'find { wanted => sub { print canonpath $_ if /\.pm\z/ }, no_chdir => 1 }, @INC'

Dec, Oct, Hex

# dec --> oct
$oct = sprintf("%o", $dec);

# oct --> dec
$dec = oct($oct);

# dec --> hex
$hex = sprintf("%x", $dec);

# hex --> dec
$dec = hex($hex);