perlcheat - Perl 5 Cheat Sheet
This 'cheat sheet' is a handy reference, meant for beginning
Perl programmers. Not everything is mentioned, but
194 features may already be overwhelming.
The sheet [Toc] [Back]
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 0 /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
list ops () capture REGEX CHARCLASSES
not (?:) no capture . ==0[^0
and [] character class == [0
or xor | alternation 48[A-Za-z0-9_]
word boundary == [0-9]
string end and 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
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.
Juerd Waalboer <[email protected]>, with the help of many
Perl Monks.
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 v5.8.5 2002-11-06 3 [ Back ] |
