PERLCHEAT(1)						 Perl Programmers Reference Guide					      PERLCHEAT(1)

NAME

       perlcheat - Perl 5 Cheat Sheet

DESCRIPTION

       This 'cheat sheet' is a handy reference, meant for beginning Perl programmers. Not everything is mentioned, but 195 features may already be
       overwhelming.

   The sheet
	 CONTEXTS  SIGILS	      ARRAYS	    HASHES
	 void	   $scalar   whole:   @array	    %hash
	 scalar    @array    slice:   @array[0, 2]  @hash{'a', 'b'}
	 list	   %hash     element: $array[0]     $hash{'a'}
		   &sub
		   *glob    SCALAR VALUES
			    number, string, reference, glob, undef
	 REFERENCES
	      references      $$foo[1]       aka $foo->[1]
	 $@%&* dereference     $$foo{bar}     aka $foo->{bar}
	 []    anon. arrayref  ${$$foo[1]}[2] aka $foo->[1]->[2]
	 {}    anon. hashref   ${$$foo[1]}[2] aka $foo->[1][2]
	 ()   list of refs
				 NUMBERS vs STRINGS  LINKS
	 OPERATOR PRECEDENCE	 =	    =	     perl.plover.com
	 ->			 +	    .	     search.cpan.org
	 ++ --			 == !=	    eq ne	  cpan.org
	 **			 < > <= >=  lt gt le ge   pm.org
	 ! ~  u+ u-		 <=>	    cmp 	  tpj.com
	 =~ !~						  perldoc.com
	 * / % x		 SYNTAX
	 + - .			 for	(LIST) { }, for (a;b;c) { }
	 << >>			 while	( ) { }, until ( ) { }
	 named uops		 if	( ) { } elsif ( ) { } else { }
	 < > <= >= lt gt le ge	 unless ( ) { } elsif ( ) { } else { }
	 == != <=> eq ne cmp ~~  for equals foreach (ALWAYS)
	 &
	 | ^		  REGEX METACHARS	     REGEX MODIFIERS
	 &&		  ^	string begin	     /i case insens.
	 || //		  $	str. end (before 
) /m line based ^$
	 .. ... 	  +	one or more	     /s . includes 

	 ?:		  *	zero or more	     /x ign. wh.space
	 = += -= *= etc.  ?	zero or one	     /g global
	 , =>		  {3,7} repeat in range      /o cmpl pat. once
	 list ops	  ()	capture
	 not		  (?:)	no capture	 REGEX CHARCLASSES
	 and		  []	character class  .  == [^
]
	 or xor 	  |	alternation	 s == whitespace
			  	word boundary	 w == word characters
			  z	string end	 d == digits
	 DO					 S, W and D negate
	 use strict;	    DON'T
	 use warnings;	    "$foo"	     LINKS
	 my $var;	    $$variable_name  perl.com
	 open() or die $!;  `$userinput`     use.perl.org
	 use Modules;	    /$userinput/     perl.apache.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

ACKNOWLEDGEMENTS

       The first version of this document appeared on Perl Monks, where several people had useful suggestions. Thank you, Perl Monks.

       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.

AUTHOR

       Juerd Waalboer <#####@juerd.nl>, with the help of many Perl Monks.

SEE ALSO

	http://perlmonks.org/?node_id=216602	  the original PM post
	http://perlmonks.org/?node_id=238031	  Damian Conway's Perl 6 version
	http://juerd.nl/site.plp/perlcheat	  home of the Perl Cheat Sheet

perl v5.12.1							    2010-04-26							      PERLCHEAT(1)