GSP
Quick Navigator

Search Site

Unix VPS
A - Starter
B - Basic
C - Preferred
D - Commercial
MPS - Dedicated
Previous VPSs
* Sign Up! *

Support
Contact Us
Online Help
Handbooks
Domain Status
Man Pages

FAQ
Virtual Servers
Pricing
Billing
Technical

Network
Facilities
Connectivity
Topology Map

Miscellaneous
Server Agreement
Year 2038
Credits
 

USA Flag

 

 

Man Pages


Manual Reference Pages  -  PERLCHEAT (1)

.ds Aq ’

NAME

perlcheat - Perl 5 Cheat Sheet

CONTENTS

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  ref        ARRAYS        HASHES
  void      $scalar SCALAR     @array        %hash
  scalar    @array  ARRAY      @array[0, 2]  @hash{a, b}
  list      %hash   HASH       $array[0]     $hash{a}
            &sub    CODE
            *glob   GLOB       SCALAR VALUES
                    FORMAT     number, string, ref, glob, undef
  REFERENCES
  \      reference       $$foo[1]       aka $foo->[1]
  $@%&*  dereference     $$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
                         SYNTAX
  OPERATOR PRECEDENCE    foreach (LIST) { }     for (a;b;c) { }
  ->                     while   (e) { }        until (e)   { }
  ++ --                  if      (e) { } elsif (e) { } else { }
  **                     unless  (e) { } elsif (e) { } else { }
  ! ~ \ u+ u-            given   (e) { when (e) {} default {} }
  =~ !~
  * / % x                 NUMBERS vs STRINGS  FALSE vs TRUE
  + - .                   =          =        undef, "", 0, "0"
  << >>                   +          .        anything else
  named uops              == !=      eq ne
  < > <= >= lt gt le ge   < > <= >=  lt gt le ge
  == != <=> eq ne cmp ~~  <=>        cmp
  &
  | ^             REGEX MODIFIERS       REGEX METACHARS
  &&              /i case insensitive   ^      string begin
  || //           /m line based ^$      $      str end (bfr \n)
  .. ...          /s . includes \n      +      one or more
  ?:              /x ignore wh.space    *      zero or more
  = += last goto  /p preserve           ?      zero or one
  , =>            /a ASCII    /aa safe  {3,7}  repeat in range
  list ops        /l locale   /d  dual  |      alternation
  not             /u Unicode            []     character class
  and             /e evaluate /ee rpts  \b     boundary
  or xor          /g global             \z     string end
                  /o compile pat once   ()     capture
  DEBUG                                 (?:p)  no capture
  -MO=Deparse     REGEX CHARCLASSES     (?#t)  comment
  -MO=Terse       .   [^\n]             (?=p)  ZW pos ahead
  -D##            \s  whitespace        (?!p)  ZW neg ahead
  -d:Trace        \w  word chars        (?<=p) ZW pos behind \K
                  \d  digits            (?<!p) ZW neg behind
  CONFIGURATION   \pP named property    (?>p)  no backtrack
  perl -V:ivsize  \h  horiz.wh.space    (?|p|p)branch reset
                  \R  linebreak         (?<n>p)named capture
                  \S \W \D \H negate    \g{n}  ref to named cap
                                        \K     keep left part
  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               10 hinthash    @INC  include paths
  11 blksz               3..10 only     @_    subroutine args
  12 blcks               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

o <http://perlmonks.org/?node_id=216602> - the original PM post
o <http://perlmonks.org/?node_id=238031> - Damian Conway’s Perl 6 version
o <http://juerd.nl/site.plp/perlcheat> - home of the Perl Cheat Sheet
Search for    or go to Top of page |  Section 1 |  Main Index


perl v5.22.1 PERLCHEAT (1) 2015-10-17

Powered by GSP Visit the GSP FreeBSD Man Page Interface.
Output converted with manServer 1.07.