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.\" -*- mode: troff; coding: utf-8 -*-
.\" Automatically generated by Pod::Man 5.01 (Pod::Simple 3.43)
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.\"
.\" If the F register is >0, we'll generate index entries on stderr for
.\" titles (.TH), headers (.SH), subsections (.SS), items (.Ip), and index
.\" entries marked with X<> in POD. Of course, you'll have to process the
.\" output yourself in some meaningful fashion.
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.\" Avoid warning from groff about undefined register 'F'.
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.\" ========================================================================
.\"
.IX Title "PERLCHEAT 1"
.TH PERLCHEAT 1 2023-11-28 "perl v5.38.2" "Perl Programmers Reference Guide"
.\" For nroff, turn off justification. Always turn off hyphenation; it makes
.\" way too many mistakes in technical documents.
.if n .ad l
.nh
.SH NAME
perlcheat \- Perl 5 Cheat Sheet
.SH DESCRIPTION
.IX Header "DESCRIPTION"
This 'cheat sheet' is a handy reference, meant for beginning Perl
programmers. Not everything is mentioned, but 195 features may
already be overwhelming.
.SS "The sheet"
.IX Subsection "The sheet"
.Vb 10
\& CONTEXTS SIGILS ref ARRAYS HASHES
\& void $scalar SCALAR @array %hash
\& scalar @array ARRAY @array[0, 2] @hash{\*(Aqa\*(Aq, \*(Aqb\*(Aq}
\& list %hash HASH $array[0] $hash{\*(Aqa\*(Aq}
\& &sub CODE
\& *glob GLOB SCALAR VALUES
\& FORMAT number, string, ref, glob, undef
\& REFERENCES
\& \e 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 $foo\->[1][2]
\& \e() list of refs
\& SYNTAX
\& OPERATOR PRECEDENCE foreach (LIST) { } for (a;b;c) { }
\& \-> while (e) { } until (e) { }
\& ++ \-\- if (e) { } elsif (e) { } else { }
\& ** unless (e) { } elsif (e) { } else { }
\& ! ~ \e u+ u\- given (e) { when (e) {} default {} }
\& =~ !~
\& * / % x NUMBERS vs STRINGS FALSE vs TRUE
\& + \- . = = undef, "", 0, "0"
\& << >> + . anything else
\& named uops == != eq ne
\& < > <= >= lt gt le ge < > <= >= lt gt le ge
\& == != <=> eq ne cmp ~~ <=> cmp
\& &
\& | ^ REGEX MODIFIERS REGEX METACHARS
\& && /i case insensitive ^ string begin
\& || // /m line based ^$ $ str end (bfr \en)
\& .. ... /s . includes \en + one or more
\& ?: /x /xx ign. 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 \eb boundary
\& or xor /g global \ez string end
\& /o compile pat once () capture
\& DEBUG (?:p) no capture
\& \-MO=Deparse REGEX CHARCLASSES (?#t) comment
\& \-MO=Terse . [^\en] (?=p) ZW pos ahead
\& \-D## \es whitespace (?!p) ZW neg ahead
\& \-d:Trace \ew word chars (?<=p) ZW pos behind \eK
\& \ed digits (?<!p) ZW neg behind
\& CONFIGURATION \epP named property (?>p) no backtrack
\& perl \-V:ivsize \eh horiz.wh.space (?|p|p)branch reset
\& \eR linebreak (?<n>p)named capture
\& \eS \eW \eD \eH negate \eg{n} ref to named cap
\& \eK 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 $\e 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
.Ve
.SH ACKNOWLEDGEMENTS
.IX Header "ACKNOWLEDGEMENTS"
The first version of this document appeared on Perl Monks, where several
people had useful suggestions. Thank you, Perl Monks.
.PP
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
Raku version to show that Perl will stay Perl.
.SH AUTHOR
.IX Header "AUTHOR"
Juerd Waalboer <#####@juerd.nl>, with the help of many Perl Monks.
.SH "SEE ALSO"
.IX Header "SEE ALSO"
.IP \(bu 4
<https://perlmonks.org/?node_id=216602> \- the original PM post
.IP \(bu 4
<https://perlmonks.org/?node_id=238031> \- Damian Conway's Raku version
.IP \(bu 4
<https://juerd.nl/site.plp/perlcheat> \- home of the Perl Cheat Sheet
|
