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Commit	Line	Data
	1	=head1 NAME
	2
	3	perlcheat - Perl 5 Cheat Sheet
	4
	5	=head1 DESCRIPTION
	6
	7	This 'cheat sheet' is a handy reference, meant for beginning Perl
	8	programmers. Not everything is mentioned, but 195 features may
	9	already be overwhelming.
	10
	11	=head2 The sheet
	12
	13	CONTEXTS SIGILS ref ARRAYS HASHES
	14	void $scalar SCALAR @array %hash
	15	scalar @array ARRAY @array[0, 2] @hash{'a', 'b'}
	16	list %hash HASH $array[0] $hash{'a'}
	17	&sub CODE
	18	*glob GLOB SCALAR VALUES
	19	FORMAT number, string, ref, glob, undef
	20	REFERENCES
	21	\ reference $$foo[1] aka $foo->[1]
	22	$@%&* dereference $$foo{bar} aka $foo->{bar}
	23	[] anon. arrayref ${$$foo[1]}[2] aka $foo->[1]->[2]
	24	{} anon. hashref ${$$foo[1]}[2] aka $foo->[1][2]
	25	\() list of refs
	26	SYNTAX
	27	OPERATOR PRECEDENCE foreach (LIST) { } for (a;b;c) { }
	28	-> while (e) { } until (e) { }
	29	++ -- if (e) { } elsif (e) { } else { }
	30	** unless (e) { } elsif (e) { } else { }
	31	! ~ \ u+ u- given (e) { when (e) {} default {} }
	32	=~ !~
	33	* / % x NUMBERS vs STRINGS FALSE vs TRUE
	34	+ - . = = undef, "", 0, "0"
	35	<< >> + . anything else
	36	named uops == != eq ne
	37	< > <= >= lt gt le ge < > <= >= lt gt le ge
	38	== != <=> eq ne cmp ~~ <=> cmp
	39	&
	40	\| ^ REGEX MODIFIERS REGEX METACHARS
	41	&& /i case insensitive ^ string begin
	42	\|\| // /m line based ^$ $ str end (bfr \n)
	43	.. ... /s . includes \n + one or more
	44	?: /x ignore wh.space * zero or more
	45	= += last goto /p preserve ? zero or one
	46	, => /a ASCII /aa safe {3,7} repeat in range
	47	list ops /l locale /d dual \| alternation
	48	not /u Unicode [] character class
	49	and /e evaluate /ee rpts \b word boundary
	50	or xor /g global \z string end
	51	/o compile pat once () capture
	52	DEBUG (?:p) no capture
	53	-MO=Deparse REGEX CHARCLASSES (?#t) comment
	54	-MO=Terse . [^\n] (?=p) ZW pos ahead
	55	-D## \s whitespace (?!p) ZW neg ahead
	56	-d:Trace \w word chars (?<=p) ZW pos behind \K
	57	\d digits (?<!p) ZW neg behind
	58	CONFIGURATION \pP named property (?>p) no backtrack
	59	perl -V:ivsize \h horiz.wh.space (?\|p\|p)branch reset
	60	\R linebreak (?<n>p)named capture
	61	\S \W \D \H negate \g{n} ref to named cap
	62	\K keep left part
	63	FUNCTION RETURN LISTS
	64	stat localtime caller SPECIAL VARIABLES
	65	0 dev 0 second 0 package $_ default variable
	66	1 ino 1 minute 1 filename $0 program name
	67	2 mode 2 hour 2 line $/ input separator
	68	3 nlink 3 day 3 subroutine $\ output separator
	69	4 uid 4 month-1 4 hasargs $\| autoflush
	70	5 gid 5 year-1900 5 wantarray $! sys/libcall error
	71	6 rdev 6 weekday 6 evaltext $@ eval error
	72	7 size 7 yearday 7 is_require $$ process ID
	73	8 atime 8 is_dst 8 hints $. line number
	74	9 mtime 9 bitmask @ARGV command line args
	75	10 ctime 10 hinthash @INC include paths
	76	11 blksz 3..10 only @_ subroutine args
	77	12 blcks with EXPR %ENV environment
	78
	79	=head1 ACKNOWLEDGEMENTS
	80
	81	The first version of this document appeared on Perl Monks, where several
	82	people had useful suggestions. Thank you, Perl Monks.
	83
	84	A special thanks to Damian Conway, who didn't only suggest important changes,
	85	but also took the time to count the number of listed features and make a
	86	Perl 6 version to show that Perl will stay Perl.
	87
	88	=head1 AUTHOR
	89
	90	Juerd Waalboer <#####@juerd.nl>, with the help of many Perl Monks.
	91
	92	=head1 SEE ALSO
	93
	94	=over 4
	95
	96	=item *
	97
	98	L<http://perlmonks.org/?node_id=216602> - the original PM post
	99
	100	=item *
	101
	102	L<http://perlmonks.org/?node_id=238031> - Damian Conway's Perl 6 version
	103
	104	=item *
	105
	106	L<http://juerd.nl/site.plp/perlcheat> - home of the Perl Cheat Sheet
	107
	108	=back