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<h1><a>perlcheat - Perl 5 Cheat Sheet</a></h1>
<p><a name="__index__"></a></p>

<!-- INDEX BEGIN -->

<ul>

	<li><a href="#name">NAME</a></li>
	<li><a href="#description">DESCRIPTION</a></li>
	<ul>

		<li><a href="#the_sheet">The sheet</a></li>
	</ul>

	<li><a href="#acknowledgements">ACKNOWLEDGEMENTS</a></li>
	<li><a href="#author">AUTHOR</a></li>
	<li><a href="#see_also">SEE ALSO</a></li>
</ul>
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<p>
</p>
<h1><a name="name">NAME</a></h1>
<p>perlcheat - Perl 5 Cheat Sheet</p>
<p>
</p>
<hr />
<h1><a name="description">DESCRIPTION</a></h1>
<p>This 'cheat sheet' is a handy reference, meant for beginning Perl
programmers. Not everything is mentioned, but 194 features may
already be overwhelming.</p>
<p>
</p>
<h2><a name="the_sheet">The sheet</a></h2>
<pre>
  <span class="variable">CONTEXTS</span>  <span class="variable">SIGILS</span>             <span class="variable">ARRAYS</span>        <span class="variable">HASHES</span>
  <span class="variable">void</span>      <span class="variable">$scalar</span>   <span class="variable">whole</span><span class="operator">:</span>   <span class="variable">@array</span>        <span class="variable">%hash</span>
  <span class="keyword">scalar</span>    <span class="variable">@array</span>    <span class="variable">slice</span><span class="operator">:</span>   <span class="variable">@array</span><span class="operator">[</span><span class="number">0</span><span class="operator">,</span> <span class="number">2</span><span class="operator">]</span>  <span class="variable">@hash</span><span class="operator">{</span><span class="string">'a'</span><span class="operator">,</span> <span class="string">'b'</span><span class="operator">}</span>
  <span class="variable">list</span>      <span class="variable">%hash</span>     <span class="variable">element</span><span class="operator">:</span> <span class="variable">$array</span><span class="operator">[</span><span class="number">0</span><span class="operator">]</span>     <span class="variable">$hash</span><span class="operator">{</span><span class="string">'a'</span><span class="operator">}</span>
            <span class="operator">&amp;</span><span class="variable">sub</span>
            <span class="variable">*glob</span>    <span class="variable">SCALAR</span> <span class="variable">VALUES</span>
                     <span class="variable">number</span><span class="operator">,</span> <span class="variable">string</span><span class="operator">,</span> <span class="variable">reference</span><span class="operator">,</span> <span class="keyword">glob</span><span class="operator">,</span> <span class="keyword">undef</span>
  <span class="variable">REFERENCES</span>
  <span class="operator">\</span>     <span class="variable">references</span>      <span class="variable">$$foo</span><span class="operator">[</span><span class="number">1</span><span class="operator">]</span>       <span class="variable">aka</span> <span class="variable">$foo</span><span class="operator">-&gt;</span><span class="operator">[</span><span class="number">1</span><span class="operator">]</span>
  <span class="variable">$@</span><span class="variable">%&amp;</span><span class="operator">*</span> <span class="variable">dereference</span>     <span class="variable">$$foo</span><span class="operator">{</span><span class="string">bar</span><span class="operator">}</span>     <span class="variable">aka</span> <span class="variable">$foo</span><span class="operator">-&gt;</span><span class="operator">{</span><span class="string">bar</span><span class="operator">}</span>
  <span class="operator">[]</span>    <span class="variable">anon</span><span class="operator">.</span> <span class="variable">arrayref</span>  <span class="variable">$</span><span class="operator">{</span><span class="variable">$$foo</span><span class="operator">[</span><span class="number">1</span><span class="operator">]}[</span><span class="number">2</span><span class="operator">]</span> <span class="variable">aka</span> <span class="variable">$foo</span><span class="operator">-&gt;</span><span class="operator">[</span><span class="number">1</span><span class="operator">]</span><span class="operator">-&gt;</span><span class="operator">[</span><span class="number">2</span><span class="operator">]</span>
  <span class="operator">{}</span>    <span class="variable">anon</span><span class="operator">.</span> <span class="variable">hashref</span>   <span class="variable">$</span><span class="operator">{</span><span class="variable">$$foo</span><span class="operator">[</span><span class="number">1</span><span class="operator">]}[</span><span class="number">2</span><span class="operator">]</span> <span class="variable">aka</span> <span class="variable">$foo</span><span class="operator">-&gt;</span><span class="operator">[</span><span class="number">1</span><span class="operator">][</span><span class="number">2</span><span class="operator">]</span>
  <span class="operator">\()</span>   <span class="variable">list</span> <span class="variable">of</span> <span class="variable">refs</span>
                          <span class="variable">NUMBERS</span> <span class="variable">vs</span> <span class="variable">STRINGS</span>  <span class="variable">LINKS</span>
  <span class="variable">OPERATOR</span> <span class="variable">PRECEDENCE</span>     <span class="operator">=</span>          <span class="operator">=</span>        <span class="variable">perl</span><span class="operator">.</span><span class="variable">plover</span><span class="operator">.</span><span class="variable">com</span>
  <span class="operator">-&gt;</span>                      +          <span class="operator">.</span>        <span class="variable">search</span><span class="operator">.</span><span class="variable">cpan</span><span class="operator">.</span><span class="variable">org</span>
  <span class="operator">++</span> <span class="operator">--</span>                   <span class="operator">==</span> <span class="operator">!=</span>      <span class="keyword">eq</span> <span class="keyword">ne</span>         <span class="variable">cpan</span><span class="operator">.</span><span class="variable">org</span>
  <span class="operator">**</span>                      <span class="operator">&lt;</span> <span class="operator">&gt;</span> <span class="operator">&lt;=</span> <span class="operator">&gt;=</span>  <span class="keyword">lt</span> <span class="keyword">gt</span> <span class="keyword">le</span> <span class="keyword">ge</span>   <span class="variable">pm</span><span class="operator">.</span><span class="variable">org</span>
  <span class="operator">!</span> <span class="operator">~</span> <span class="operator">\</span> <span class="variable">u</span><span class="operator">+</span> <span class="variable">u</span><span class="operator">-</span>             <span class="operator">&lt;=&gt;</span>        <span class="keyword">cmp</span>           <span class="variable">tpj</span><span class="operator">.</span><span class="variable">com</span>
  <span class="operator">=~</span> <span class="operator">!~</span>                                            <span class="variable">perldoc</span><span class="operator">.</span><span class="variable">com</span>
  <span class="operator">*</span> <span class="operator">/</span> <span class="operator">% x</span>                 <span class="variable">SYNTAX</span>
  <span class="operator">+</span> <span class="operator">-</span> <span class="operator">.</span>                   <span class="keyword">for</span>    <span class="operator">(</span><span class="variable">LIST</span><span class="operator">)</span> <span class="operator">{</span> <span class="operator">},</span> <span class="keyword">for</span> <span class="operator">(</span><span class="variable">a</span><span class="operator">;</span><span class="variable">b</span><span class="operator">;</span><span class="variable">c</span><span class="operator">)</span> <span class="operator">{</span> <span class="operator">}</span>
  <span class="operator">&lt;&lt;</span><span class="default"> </span><span class="operator">&gt;&gt;</span>                   <span class="keyword">while</span>  <span class="operator">(</span> <span class="operator">)</span> <span class="operator">{</span> <span class="operator">},</span> <span class="keyword">until</span> <span class="operator">(</span> <span class="operator">)</span> <span class="operator">{</span> <span class="operator">}</span><span class="string">
  named uops              if     ( ) { } elsif ( ) { } else { }
  &lt; &gt; &lt;= &gt;= lt gt le ge   unless ( ) { } elsif ( ) { } else { }
  == != &lt;=&gt; eq ne cmp     for equals foreach (ALWAYS)
  &amp;
  | ^              REGEX METACHARS            REGEX MODIFIERS
  &amp;&amp;               ^     string begin         /i case insens.
  ||               $     str. end (before \n) /m line based ^$
  .. ...           +     one or more          /s . includes \n
  ?:               *     zero or more         /x ign. wh.space
  = += -= *= etc.  ?     zero or one          /g global
  , =&gt;             {3,7} repeat in range
  list ops         ()    capture          REGEX CHARCLASSES
  not              (?:)  no capture       .  == [^\n]
  and              []    character class  \s == [\x20\f\t\r\n]
  or xor           |     alternation      \w == [A-Za-z0-9_]
                   \b    word boundary    \d == [0-9]
                   \z    string end       \S, \W and \D negate
  DO
  use strict;        DON'T            LINKS
  use warnings;      "$foo"           perl.com
  my $var;           $$variable_name  perlmonks.org
  open() or die $!;  `$userinput`     use.perl.org
  use Modules;       /$userinput/     perl.apache.org
                                      parrotcode.org
  FUNCTION RETURN LISTS
  stat      localtime    caller         SPECIAL VARIABLES
   0 dev    0 second     0 package      $_    default variable
   1 ino    1 minute     1 filename     $0    program name
   2 mode   2 hour       2 line         $/    input separator
   3 nlink  3 day        3 subroutine   $\    output separator
   4 uid    4 month-1    4 hasargs      $|    autoflush
   5 gid    5 year-1900  5 wantarray    $!    sys/libcall error
   6 rdev   6 weekday    6 evaltext     $@    eval error
   7 size   7 yearday    7 is_require   $$    process ID
   8 atime  8 is_dst     8 hints        $.    line number
   9 mtime               9 bitmask      @ARGV command line args
  10 ctime  just use                    @INC  include paths
  11 blksz  POSIX::      3..9 only      @_    subroutine args
  12 blcks  strftime!    with EXPR      %ENV  environment
  </span>
</pre>
<p>
</p>
<hr />
<h1><a name="acknowledgements">ACKNOWLEDGEMENTS</a></h1>
<p>The first version of this document appeared on Perl Monks, where several
people had useful suggestions. Thank you, Perl Monks.</p>
<p>A special thanks to Damian Conway, who didn't only suggest important changes,
but also took the time to count the number of listed features and make a
Perl 6 version to show that Perl will stay Perl.</p>
<p>
</p>
<hr />
<h1><a name="author">AUTHOR</a></h1>
<p>Juerd Waalboer &lt;<a href="mailto:juerd@cpan.org">juerd@cpan.org</a>&gt;, with the help of many Perl Monks.</p>
<p>
</p>
<hr />
<h1><a name="see_also">SEE ALSO</a></h1>
<pre>
 <a href="http://perlmonks.org/?node_id=216602">http://perlmonks.org/?node_id=216602</a>      the original PM post
 <a href="http://perlmonks.org/?node_id=238031">http://perlmonks.org/?node_id=238031</a>      Damian Conway's Perl 6 version
 <a href="http://juerd.nl/site.plp/">http://juerd.nl/site.plp/</a><a href="../../lib/Pod/perlcheat.html">perlcheat</a>        home of the Perl Cheat Sheet</pre>

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