CONTENTS

• Pragmatic Modules
• Standard Modules

#Pragmatic Modules

They work somewhat like compiler directives (pragmata) in that they tend to affect the compilation of your program, and thus will usually work well only when used within ause, orno. Most of these are lexically scoped, so an inner BLOCK may countermand them by saying:

no integer;no strict 'refs';no warnings;

which lasts until the end of that BLOCK.

Some pragmas are lexically scoped--typically those that affect the$^H hints variable. Others affect the current package instead, likeuse vars anduse subs, which allow you to predeclare a variables or subroutines within a particularfile rather than just a block. Such declarations are effective for the entire file for which they were declared. You cannot rescind them withno vars orno subs.

The following pragmas are defined (and have their own documentation).

• attributes - Get/set subroutine or variable attributes

• attrs - Set/get attributes of a subroutine (deprecated)

• autouse - Postpone load of modules until a function is used

• base - Establish IS-A relationship with base class at compile time

• bigint - Transparent BigInteger support for Perl

• bignum - Transparent BigNumber support for Perl

• bigrat - Transparent BigNumber/BigRational support for Perl

• blib - Use MakeMaker's uninstalled version of a package

• bytes - Force byte semantics rather than character semantics

• charnames - Define character names for\N{named} string literal escapes

• constant - Declare constants

• diagnostics - Produce verbose warning diagnostics

• encoding - Allows you to write your script in non-ascii or non-utf8

• fields - Compile-time class fields

• filetest - Control the filetest permission operators

• if -use a Perl module if a condition holds

• integer - Use integer arithmetic instead of floating point

• less - Request less of something from the compiler

• lib - Manipulate @INC at compile time

• locale - Use and avoid POSIX locales for built-in operations

• open - Set default PerlIO layers for input and output

• ops - Restrict unsafe operations when compiling

• overload - Package for overloading perl operations

• re - Alter regular expression behaviour

• sigtrap - Enable simple signal handling

• sort - Control sort() behaviour

• strict - Restrict unsafe constructs

• subs - Predeclare sub names

• threads - Perl extension allowing use of interpreter based threads from perl

• threads::shared - Perl extension for sharing data structures between threads

• utf8 - Enable/disable UTF-8 (or UTF-EBCDIC) in source code

• vars - Predeclare global variable names (obsolete)

• vmsish - Control VMS-specific language features

• warnings - Control optional warnings

• warnings::register - Warnings import function

#Standard Modules

Standard, bundled modules are all expected to behave in a well-defined manner with respect to namespace pollution because they use the Exporter module. See their own documentation for details.

It's possible that not all modules listed below are installed on your system. For example, the GDBM_File module will not be installed if you don't have the gdbm library.

• AnyDBM_File - Provide framework for multiple DBMs

• Attribute::Handlers - Simpler definition of attribute handlers

• AutoLoader - Load subroutines only on demand

• AutoSplit - Split a package for autoloading

• B - The Perl Compiler

• B::Asmdata - Autogenerated data about Perl ops, used to generate bytecode

• B::Assembler - Assemble Perl bytecode

• B::Bblock - Walk basic blocks

• B::Bytecode - Perl compiler's bytecode backend

• B::C - Perl compiler's C backend

• B::CC - Perl compiler's optimized C translation backend

• B::Concise - Walk Perl syntax tree, printing concise info about ops

• B::Debug - Walk Perl syntax tree, printing debug info about ops

• B::Deparse - Perl compiler backend to produce perl code

• B::Disassembler - Disassemble Perl bytecode

• B::Lint - Perl lint

• B::Showlex - Show lexical variables used in functions or files

• B::Stackobj - Helper module for CC backend

• B::Stash - Show what stashes are loaded

• B::Terse - Walk Perl syntax tree, printing terse info about ops

• B::Xref - Generates cross reference reports for Perl programs

• Benchmark - Benchmark running times of Perl code

• ByteLoader - Load byte compiled perl code

• CGI - Simple Common Gateway Interface Class

• CGI::Apache - Backward compatibility module for CGI.pm

• CGI::Carp - CGI routines for writing to the HTTPD (or other) error log

• CGI::Cookie - Interface to Netscape Cookies

• CGI::Fast - CGI Interface for Fast CGI

• CGI::Pretty - Module to produce nicely formatted HTML code

• CGI::Push - Simple Interface to Server Push

• CGI::Switch - Backward compatibility module for defunct CGI::Switch

• CGI::Util - Internal utilities used by CGI module

• CPAN - Query, download and build perl modules from CPAN sites

• CPAN::FirstTime - Utility for CPAN::Config file Initialization

• CPAN::Nox - Wrapper around CPAN.pm without using any XS module

• Carp - Warn of errors (from perspective of caller)

• Carp::Heavy - No user serviceable parts inside

• Class::ISA - Report the search path for a class's ISA tree

• Class::Struct - Declare struct-like datatypes as Perl classes

• Config - Access Perl configuration information

• Cwd - Get pathname of current working directory

• DB - Programmatic interface to the Perl debugging API (draft, subject to

• DB_File - Perl5 access to Berkeley DB version 1.x

• Data::Dumper - Stringified perl data structures, suitable for both printing andeval

• Devel::DProf - A Perl code profiler

• Devel::PPPort - Perl/Pollution/Portability

• Devel::Peek - A data debugging tool for the XS programmer

• Devel::SelfStubber - Generate stubs for a SelfLoading module

• Digest - Modules that calculate message digests

• Digest::MD5 - Perl interface to the MD5 Algorithm

• Digest::base - Digest base class

• DirHandle - Supply object methods for directory handles

• Dumpvalue - Provides screen dump of Perl data.

• DynaLoader - Dynamically load C libraries into Perl code

• Encode - Character encodings

• Encode::Alias - Alias definitions to encodings

• Encode::Byte - Single Byte Encodings

• Encode::CJKConstants - Internally used by Encode::??::ISO_2022_*

• Encode::CN - China-based Chinese Encodings

• Encode::CN::HZ - Internally used by Encode::CN

• Encode::Config - Internally used by Encode

• Encode::EBCDIC - EBCDIC Encodings

• Encode::Encoder - Object Oriented Encoder

• Encode::Encoding - Encode Implementation Base Class

• Encode::Guess - Guesses encoding from data

• Encode::JP - Japanese Encodings

• Encode::JP::H2Z - Internally used by Encode::JP::2022_JP*

• Encode::JP::JIS7 - Internally used by Encode::JP

• Encode::KR - Korean Encodings

• Encode::KR::2022_KR - Internally used by Encode::KR

• Encode::MIME::Header - MIME 'B' and 'Q' header encoding

• Encode::PerlIO - A detailed document on Encode and PerlIO

• Encode::Supported - Encodings supported by Encode

• Encode::Symbol - Symbol Encodings

• Encode::TW - Taiwan-based Chinese Encodings

• Encode::Unicode - Various Unicode Transformation Formats

• Encode::Unicode::UTF7 - UTF-7 encoding

• English - Use nice English (or awk) names for ugly punctuation variables

• Env - Perl module that imports environment variables as scalars or arrays

• Errno - System errno constants

• Exporter - Implements default import method for modules

• Exporter::Heavy - Exporter guts

• ExtUtils::Command - Utilities to replace common UNIX commands in Makefiles etc.

• ExtUtils::Command::MM - Commands for the MM's to use in Makefiles

• ExtUtils::Constant - Generate XS code to import C header constants

• ExtUtils::Embed - Utilities for embedding Perl in C/C++ applications

• ExtUtils::Install - Install files from here to there

• ExtUtils::Installed - Inventory management of installed modules

• ExtUtils::Liblist - Determine libraries to use and how to use them

• ExtUtils::MM - OS adjusted ExtUtils::MakeMaker subclass

• ExtUtils::MM_Any - Platform-agnostic MM methods

• ExtUtils::MM_BeOS - Methods to override UN*X behaviour in ExtUtils::MakeMaker

• ExtUtils::MM_Cygwin - Methods to override UN*X behaviour in ExtUtils::MakeMaker

• ExtUtils::MM_DOS - DOS specific subclass of ExtUtils::MM_Unix

• ExtUtils::MM_MacOS - Methods to override UN*X behaviour in ExtUtils::MakeMaker

• ExtUtils::MM_NW5 - Methods to override UN*X behaviour in ExtUtils::MakeMaker

• ExtUtils::MM_OS2 - Methods to override UN*X behaviour in ExtUtils::MakeMaker

• ExtUtils::MM_UWIN - U/WIN specific subclass of ExtUtils::MM_Unix

• ExtUtils::MM_Unix - Methods used by ExtUtils::MakeMaker

• ExtUtils::MM_VMS - Methods to override UN*X behaviour in ExtUtils::MakeMaker

• ExtUtils::MM_Win32 - Methods to override UN*X behaviour in ExtUtils::MakeMaker

• ExtUtils::MM_Win95 - Method to customize MakeMaker for Win9X

• ExtUtils::MY - ExtUtils::MakeMaker subclass for customization

• ExtUtils::MakeMaker - Create a module Makefile

• ExtUtils::MakeMaker::FAQ - Frequently Asked Questions About MakeMaker

• ExtUtils::MakeMaker::Tutorial - Writing a module with MakeMaker

• ExtUtils::MakeMaker::bytes - Version-agnostic bytes.pm

• ExtUtils::MakeMaker::vmsish - Platform-agnostic vmsish.pm

• ExtUtils::Manifest - Utilities to write and check a MANIFEST file

• ExtUtils::Mkbootstrap - Make a bootstrap file for use by DynaLoader

• ExtUtils::Mksymlists - Write linker options files for dynamic extension

• ExtUtils::Packlist - Manage .packlist files

• ExtUtils::testlib - Add blib/* directories to @INC

• Fatal - Replace functions with equivalents which succeed or die

• Fcntl - Load the C Fcntl.h defines

• File::Basename - Split a pathname into pieces

• File::CheckTree - Run many filetest checks on a tree

• File::Compare - Compare files or filehandles

• File::Copy - Copy files or filehandles

• File::DosGlob - DOS like globbing and then some

• File::Find - Traverse a directory tree.

• File::Glob - Perl extension for BSD glob routine

• File::Path - Create or remove directory trees

• File::Spec - Portably perform operations on file names

• File::Spec::Cygwin - Methods for Cygwin file specs

• File::Spec::Epoc - Methods for Epoc file specs

• File::Spec::Functions - Portably perform operations on file names

• File::Spec::Mac - File::Spec for Mac OS (Classic)

• File::Spec::OS2 - Methods for OS/2 file specs

• File::Spec::Unix - File::Spec for Unix, base for other File::Spec modules

• File::Spec::VMS - Methods for VMS file specs

• File::Spec::Win32 - Methods for Win32 file specs

• File::Temp - Return name and handle of a temporary file safely

• File::stat - By-name interface to Perl's built-in stat() functions

• FileCache - Keep more files open than the system permits

• FileHandle - Supply object methods for filehandles

• Filter::Simple - Simplified source filtering

• Filter::Util::Call - Perl Source Filter Utility Module

• FindBin - Locate directory of original perl script

• GDBM_File - Perl5 access to the gdbm library.

• Getopt::Long - Extended processing of command line options

• Getopt::Std - Process single-character switches with switch clustering

• Hash::Util - A selection of general-utility hash subroutines

• I18N::Collate - Compare 8-bit scalar data according to the current locale

• I18N::LangTags - Functions for dealing with RFC3066-style language tags

• I18N::LangTags::List - Tags and names for human languages

• I18N::Langinfo - Query locale information

• IO - Load various IO modules

• IO::Dir - Supply object methods for directory handles

• IO::File - Supply object methods for filehandles

• IO::Handle - Supply object methods for I/O handles

• IO::Pipe - Supply object methods for pipes

• IO::Poll - Object interface to system poll call

• IO::Seekable - Supply seek based methods for I/O objects

• IO::Select - OO interface to the select system call

• IO::Socket - Object interface to socket communications

• IO::Socket::INET - Object interface for AF_INET domain sockets

• IO::Socket::UNIX - Object interface for AF_UNIX domain sockets

• IPC::Open2 - Open a process for both reading and writing

• IPC::Open3 - Open a process for reading, writing, and error handling

• IPC::SysV - SysV IPC constants

• IPC::SysV::Msg - SysV Msg IPC object class

• IPC::SysV::Semaphore - SysV Semaphore IPC object class

• List::Util - A selection of general-utility list subroutines

• Locale::Constants - Constants for Locale codes

• Locale::Country - ISO codes for country identification (ISO 3166)

• Locale::Currency - ISO three letter codes for currency identification (ISO 4217)

• Locale::Language - ISO two letter codes for language identification (ISO 639)

• Locale::Maketext - Framework for localization

• Locale::Maketext::TPJ13 - Article about software localization

• Locale::Script - ISO codes for script identification (ISO 15924)

• MIME::Base64 - Encoding and decoding of base64 strings

• MIME::Base64::QuotedPrint - Encoding and decoding of quoted-printable strings

• Math::BigFloat - Arbitrary size floating point math package

• Math::BigInt - Arbitrary size integer math package

• Math::BigInt::Calc - Pure Perl module to support Math::BigInt

• Math::BigRat - Arbitrarily big rationals

• Math::Complex - Complex numbers and associated mathematical functions

• Math::Trig - Trigonometric functions

• Memoize - Make functions faster by trading space for time

• Memoize::AnyDBM_File - Glue to provide EXISTS for AnyDBM_File for Storable use

• Memoize::Expire - Plug-in module for automatic expiration of memoized values

• Memoize::ExpireFile - Test for Memoize expiration semantics

• Memoize::ExpireTest - Test for Memoize expiration semantics

• Memoize::NDBM_File - Glue to provide EXISTS for NDBM_File for Storable use

• Memoize::SDBM_File - Glue to provide EXISTS for SDBM_File for Storable use

• Memoize::Storable - Store Memoized data in Storable database

• NDBM_File - Tied access to ndbm files

• NEXT - Provide a pseudo-class NEXT (et al) that allows method redispatch

• Net::Cmd - Network Command class (as used by FTP, SMTP etc)

• Net::Config - Local configuration data for libnet

• Net::Domain - Attempt to evaluate the current host's internet name and domain

• Net::FTP - FTP Client class

• Net::NNTP - NNTP Client class

• Net::Netrc - OO interface to users netrc file

• Net::POP3 - Post Office Protocol 3 Client class (RFC1939)

• Net::Ping - Check a remote host for reachability

• Net::SMTP - Simple Mail Transfer Protocol Client

• Net::Time - Time and daytime network client interface

• Net::hostent - By-name interface to Perl's built-in gethost*() functions

• Net::libnetFAQ - Libnet Frequently Asked Questions

• Net::netent - By-name interface to Perl's built-in getnet*() functions

• Net::protoent - By-name interface to Perl's built-in getproto*() functions

• Net::servent - By-name interface to Perl's built-in getserv*() functions

• O - Generic interface to Perl Compiler backends

• ODBM_File - Tied access to odbm files

• Opcode - Disable named opcodes when compiling perl code

• POSIX - Perl interface to IEEE Std 1003.1

• PerlIO - On demand loader for PerlIO layers and root of PerlIO::* name space

• PerlIO::encoding - Encoding layer

• PerlIO::scalar - In-memory IO, scalar IO

• PerlIO::via - Helper class for PerlIO layers implemented in perl

• PerlIO::via::QuotedPrint - PerlIO layer for quoted-printable strings

• Pod::Checker - Check pod documents for syntax errors

• Pod::Find - Find POD documents in directory trees

• Pod::Functions - Group Perl's functions a la perlfunc.pod

• Pod::Html - Module to convert pod files to HTML

• Pod::InputObjects - Objects representing POD input paragraphs, commands, etc.

• Pod::LaTeX - Convert Pod data to formatted Latex

• Pod::Man - Convert POD data to formatted *roff input

• Pod::ParseLink - Parse an L<> formatting code in POD text

• Pod::ParseUtils - Helpers for POD parsing and conversion

• Pod::Parser - Base class for creating POD filters and translators

• Pod::Perldoc::ToChecker - Let Perldoc check Pod for errors

• Pod::Perldoc::ToMan - Let Perldoc render Pod as man pages

• Pod::Perldoc::ToNroff - Let Perldoc convert Pod to nroff

• Pod::Perldoc::ToPod - Let Perldoc render Pod as ... Pod!

• Pod::Perldoc::ToRtf - Let Perldoc render Pod as RTF

• Pod::Perldoc::ToText - Let Perldoc render Pod as plaintext

• Pod::Perldoc::ToTk - Let Perldoc use Tk::Pod to render Pod

• Pod::Perldoc::ToXml - Let Perldoc render Pod as XML

• Pod::PlainText - Convert POD data to formatted ASCII text

• Pod::Plainer - Perl extension for converting Pod to old style Pod.

• Pod::Select - Extract selected sections of POD from input

• Pod::Text - Convert POD data to formatted ASCII text

• Pod::Text::Color - Convert POD data to formatted color ASCII text

• Pod::Text::Overstrike - Convert POD data to formatted overstrike text

• Pod::Text::Termcap - Convert POD data to ASCII text with format escapes

• Pod::Usage - Print a usage message from embedded pod documentation

• SDBM_File - Tied access to sdbm files

• Safe - Compile and execute code in restricted compartments

• Scalar::Util - A selection of general-utility scalar subroutines

• Search::Dict - Search for key in dictionary file

• SelectSaver - Save and restore selected file handle

• SelfLoader - Load functions only on demand

• Shell - Run shell commands transparently within perl

• Socket - Load the C socket.h defines and structure manipulators

• Storable - Persistence for Perl data structures

• Switch - A switch statement for Perl

• Symbol - Manipulate Perl symbols and their names

• Sys::Hostname - Try every conceivable way to get hostname

• Sys::Syslog - Perl interface to the UNIX syslog(3) calls

• Term::ANSIColor - Color screen output using ANSI escape sequences

• Term::Cap - Perl termcap interface

• Term::Complete - Perl word completion module

• Term::ReadLine - Perl interface to variousreadline packages.

• Test - Provides a simple framework for writing test scripts

• Test::Builder - Backend for building test libraries

• Test::Harness - Run Perl standard test scripts with statistics

• Test::Harness::Assert - Simple assert

• Test::Harness::Iterator - Internal Test::Harness Iterator

• Test::Harness::Straps - Detailed analysis of test results

• Test::More - Yet another framework for writing test scripts

• Test::Simple - Basic utilities for writing tests.

• Test::Tutorial - A tutorial about writing really basic tests

• Text::Abbrev - Create an abbreviation table from a list

• Text::Balanced - Extract delimited text sequences from strings.

• Text::ParseWords - Parse text into an array of tokens or array of arrays

• Text::Soundex - Implementation of the Soundex Algorithm as Described by Knuth

• Text::Tabs - Expand and unexpand tabs per the unix expand(1) and unexpand(1)

• Text::Wrap - Line wrapping to form simple paragraphs

• Thread - Manipulate threads in Perl (for old code only)

• Thread::Queue - Thread-safe queues

• Thread::Semaphore - Thread-safe semaphores

• Thread::Signal - Start a thread which runs signal handlers reliably (for old code)

• Thread::Specific - Thread-specific keys

• Tie::Array - Base class for tied arrays

• Tie::File - Access the lines of a disk file via a Perl array

• Tie::Handle - Base class definitions for tied handles

• Tie::Hash - Base class definitions for tied hashes

• Tie::Memoize - Add data to hash when needed

• Tie::RefHash - Use references as hash keys

• Tie::Scalar - Base class definitions for tied scalars

• Tie::SubstrHash - Fixed-table-size, fixed-key-length hashing

• Time::HiRes - High resolution alarm, sleep, gettimeofday, interval timers

• Time::Local - Efficiently compute time from local and GMT time

• Time::gmtime - By-name interface to Perl's built-in gmtime() function

• Time::localtime - By-name interface to Perl's built-in localtime() function

• Time::tm - Internal object used by Time::gmtime and Time::localtime

• UNIVERSAL - Base class for ALL classes (blessed references)

• Unicode::Collate - Unicode Collation Algorithm

• Unicode::Normalize - Unicode Normalization Forms

• Unicode::UCD - Unicode character database

• User::grent - By-name interface to Perl's built-in getgr*() functions

• User::pwent - By-name interface to Perl's built-in getpw*() functions

• Win32 - Interfaces to some Win32 API Functions

• XS::APItest - Test the perl C API

• XS::Typemap - Module to test the XS typemaps distributed with perl

• XSLoader - Dynamically load C libraries into Perl code

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