perlmodlib - Man Page

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 a use, or no.  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, like use vars and use subs, which allow you to predeclare a variables or subroutines within a particular file rather than just a block.  Such declarations are effective for the entire file for which they were declared.  You cannot rescind them with no vars or no subs.

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

attributes

Get/set subroutine or variable attributes

autodie

Replace functions with ones that succeed or die with lexical scope

autodie::exception

Exceptions from autodying functions.

autodie::exception::system

Exceptions from autodying system().

autodie::hints

Provide hints about user subroutines to autodie

autodie::skip

Skip a package when throwing autodie exceptions

autouse

Postpone load of modules until a function is used

base

Establish an ISA relationship with base classes at compile time

bigfloat

Transparent big floating point number support for Perl

bigint

Transparent big integer support for Perl

bignum

Transparent big number support for Perl

bigrat

Transparent big rational number support for Perl

blib

Use MakeMaker's uninstalled version of a package

builtin

Import built-in utility functions

bytes

Expose the individual bytes of characters

charnames

Access to Unicode character names and named character sequences; also define character names

constant

Declare constants

deprecate

Perl pragma for deprecating the inclusion of a module in core

diagnostics

Produce verbose warning diagnostics

encoding

Allows you to write your script in non-ASCII and non-UTF-8

encoding::warnings

Warn on implicit encoding conversions

experimental

Experimental features made easy

feature

Enable new features

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

lib

Manipulate @INC at compile time

locale

Use or avoid POSIX locales for built-in operations

mro

Method Resolution Order

ok

Alternative to Test::More::use_ok

open

Set default PerlIO layers for input and output

ops

Restrict unsafe operations when compiling

overload

Package for overloading Perl operations

overloading

Lexically control overloading

parent

Establish an ISA relationship with base classes at compile time

re

Alter regular expression behaviour

sigtrap

Enable simple signal handling

sort

Control sort() behaviour

stable

Experimental features made easy, once we know they're stable

strict

Restrict unsafe constructs

subs

Predeclare subroutine names

threads

Perl interpreter-based threads

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

version

Perl extension for Version Objects

vmsish

Control VMS-specific language features

warnings

Control optional warnings

warnings::register

Warnings import function

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.

Amiga::ARexx

Perl extension for ARexx support

Amiga::Exec

Perl extension for low level amiga support

AnyDBM_File

Provide framework for multiple DBMs

App::Cpan

Easily interact with CPAN from the command line

App::Prove

Implements the prove command.

App::Prove::State

State storage for the prove command.

App::Prove::State::Result

Individual test suite results.

App::Prove::State::Result::Test

Individual test results.

Archive::Tar

Module for manipulations of tar archives

Archive::Tar::File

A subclass for in-memory extracted file from Archive::Tar

Attribute::Handlers

Simpler definition of attribute handlers

AutoLoader

Load subroutines only on demand

AutoSplit

Split a package for autoloading

B

The Perl Compiler Backend

B::Concise

Walk Perl syntax tree, printing concise info about ops

B::Deparse

Perl compiler backend to produce perl code

B::Op_private

OP op_private flag definitions

B::Showlex

Show lexical variables used in functions or files

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

IO::Socket::IP

Family-neutral IP socket supporting both IPv4 and IPv6

Socket

Networking constants and support functions

Test2::Tools::Refcount

Assert reference counts on objects

CORE

Namespace for Perl's core routines

CPAN

Query, download and build perl modules from CPAN sites

CPAN::API::HOWTO

A recipe book for programming with CPAN.pm

CPAN::Debug

Internal debugging for CPAN.pm

CPAN::Distroprefs

Read and match distroprefs

CPAN::FirstTime

Utility for CPAN::Config file Initialization

CPAN::HandleConfig

Internal configuration handling for CPAN.pm

CPAN::Kwalify

Interface between CPAN.pm and Kwalify.pm

CPAN::Meta

The distribution metadata for a CPAN dist

CPAN::Meta::Converter

Convert CPAN distribution metadata structures

CPAN::Meta::Feature

An optional feature provided by a CPAN distribution

CPAN::Meta::History

History of CPAN Meta Spec changes

CPAN::Meta::History::Meta_1_0

Version 1.0 metadata specification for META.yml

CPAN::Meta::History::Meta_1_1

Version 1.1 metadata specification for META.yml

CPAN::Meta::History::Meta_1_2

Version 1.2 metadata specification for META.yml

CPAN::Meta::History::Meta_1_3

Version 1.3 metadata specification for META.yml

CPAN::Meta::History::Meta_1_4

Version 1.4 metadata specification for META.yml

CPAN::Meta::Merge

Merging CPAN Meta fragments

CPAN::Meta::Prereqs

A set of distribution prerequisites by phase and type

CPAN::Meta::Requirements

A set of version requirements for a CPAN dist

CPAN::Meta::Requirements::Range

A set of version requirements for a CPAN dist

CPAN::Meta::Spec

Specification for CPAN distribution metadata

CPAN::Meta::Validator

Validate CPAN distribution metadata structures

CPAN::Meta::YAML

Read and write a subset of YAML for CPAN Meta files

CPAN::Nox

Wrapper around CPAN.pm without using any XS module

CPAN::Plugin

Base class for CPAN shell extensions

CPAN::Plugin::Specfile

Proof of concept implementation of a trivial CPAN::Plugin

CPAN::Queue

Internal queue support for CPAN.pm

CPAN::Tarzip

Internal handling of tar archives for CPAN.pm

CPAN::Version

Utility functions to compare CPAN versions

Carp

Alternative warn and die for modules

Class::Struct

Declare struct-like datatypes as Perl classes

Compress::Raw::Bzip2

Low-Level Interface to bzip2 compression library

Compress::Raw::Zlib

Low-Level Interface to zlib or zlib-ng compression library

Compress::Zlib

Interface to zlib compression library

Config

Access Perl configuration information

Config::Extensions

Hash lookup of which core extensions were built.

Config::Perl::V

Structured data retrieval of perl -V output

Cwd

Get pathname of current working directory

DB

Programmatic interface to the Perl debugging API

DBM_Filter

Filter DBM keys/values

DBM_Filter::compress

Filter for DBM_Filter

DBM_Filter::encode

Filter for DBM_Filter

DBM_Filter::int32

Filter for DBM_Filter

DBM_Filter::null

Filter for DBM_Filter

DBM_Filter::utf8

Filter for DBM_Filter

DB_File

Perl5 access to Berkeley DB version 1.x

Data::Dumper

Stringified perl data structures, suitable for both printing and eval

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::SHA

Perl extension for SHA-1/224/256/384/512

Digest::base

Digest base class

Digest::file

Calculate digests of files

DirHandle

(obsolete) supply object methods for directory handles

Dumpvalue

Provides screen dump of Perl data.

DynaLoader

Dynamically load C libraries into Perl code

Encode

Character encodings in Perl

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::GSM0338

ETSI GSM 03.38 Encoding

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 encoding for an unstructured email header

Encode::MIME::Name

Internally used by Encode

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::CBuilder

Compile and link C code for Perl modules

ExtUtils::CBuilder::Platform::Windows

Builder class for Windows platforms

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::Constant::Base

Base class for ExtUtils::Constant objects

ExtUtils::Constant::Utils

Helper functions for ExtUtils::Constant

ExtUtils::Constant::XS

Generate C code for XS modules' 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::Utils

ExtUtils::MM methods without dependency on ExtUtils::MakeMaker

ExtUtils::MM_AIX

AIX specific subclass of ExtUtils::MM_Unix

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_Darwin

Special behaviors for OS X

ExtUtils::MM_MacOS

Once produced Makefiles for MacOS Classic

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_OS390

OS390 specific subclass of ExtUtils::MM_Unix

ExtUtils::MM_QNX

QNX specific subclass of ExtUtils::MM_Unix

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_VOS

VOS specific subclass of ExtUtils::MM_Unix

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::Config

Wrapper around Config.pm

ExtUtils::MakeMaker::FAQ

Frequently Asked Questions About MakeMaker

ExtUtils::MakeMaker::Locale

Bundled Encode::Locale

ExtUtils::MakeMaker::Tutorial

Writing a module with MakeMaker

ExtUtils::Manifest

Utilities to write and check a MANIFEST file

ExtUtils::Miniperl

Write the C code for miniperlmain.c and perlmain.c

ExtUtils::Mkbootstrap

Make a bootstrap file for use by DynaLoader

ExtUtils::Mksymlists

Write linker options files for dynamic extension

ExtUtils::PL2Bat

Batch file creation to run perl scripts on Windows

ExtUtils::Packlist

Manage .packlist files

ExtUtils::ParseXS

Converts Perl XS code into C code

ExtUtils::ParseXS::Constants

Initialization values for some globals

ExtUtils::ParseXS::Eval

Clean package to evaluate code in

ExtUtils::ParseXS::Utilities

Subroutines used with ExtUtils::ParseXS

ExtUtils::Typemaps

Read/Write/Modify Perl/XS typemap files

ExtUtils::Typemaps::Cmd

Quick commands for handling typemaps

ExtUtils::Typemaps::InputMap

Entry in the INPUT section of a typemap

ExtUtils::Typemaps::OutputMap

Entry in the OUTPUT section of a typemap

ExtUtils::Typemaps::Type

Entry in the TYPEMAP section of a typemap

ExtUtils::XSSymSet

Keep sets of symbol names palatable to the VMS linker

ExtUtils::testlib

Add blib/* directories to @INC

Fatal

Replace functions with equivalents which succeed or die

Fcntl

Various flag constants and helper functions from C's fcntl.h

File::Basename

Parse file paths into directory, filename and suffix.

File::Compare

Compare files or filehandles

File::Copy

Copy files or filehandles

File::DosGlob

DOS like globbing and then some

File::Fetch

A generic file fetching mechanism

File::Find

Traverse a directory tree.

File::Glob

Perl extension for BSD glob routine

File::GlobMapper

Extend File Glob to Allow Input and Output Files

File::Path

Create or remove directory trees

File::Spec

Portably perform operations on file names

File::Spec::AmigaOS

File::Spec for AmigaOS

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::Long::Parser

Getopt::Long object oriented interface

Getopt::Std

Process single-character switches with switch clustering

HTTP::Tiny

A small, simple, correct HTTP/1.1 client

Hash::Util

A selection of general-utility hash subroutines

Hash::Util::FieldHash

Support for Inside-Out Classes

I18N::Collate

Compare 8-bit scalar data according to the current locale

I18N::LangTags

Functions for dealing with RFC3066-style language tags

I18N::LangTags::Detect

Detect the user's language preferences

I18N::LangTags::List

Tags and names for human languages

I18N::Langinfo

Query locale information

IO

Load various IO modules

IO::Compress::Base

Base Class for IO::Compress modules

IO::Compress::Bzip2

Write bzip2 files/buffers

IO::Compress::Deflate

Write RFC 1950 files/buffers

IO::Compress::FAQ

Frequently Asked Questions about IO::Compress

IO::Compress::Gzip

Write RFC 1952 files/buffers

IO::Compress::RawDeflate

Write RFC 1951 files/buffers

IO::Compress::Zip

Write zip files/buffers

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

IO::Uncompress::AnyInflate

Uncompress zlib-based (zip, gzip) file/buffer

IO::Uncompress::AnyUncompress

Uncompress gzip, zip, bzip2, zstd, xz, lzma, lzip, lzf or lzop file/buffer

IO::Uncompress::Base

Base Class for IO::Uncompress modules

IO::Uncompress::Bunzip2

Read bzip2 files/buffers

IO::Uncompress::Gunzip

Read RFC 1952 files/buffers

IO::Uncompress::Inflate

Read RFC 1950 files/buffers

IO::Uncompress::RawInflate

Read RFC 1951 files/buffers

IO::Uncompress::Unzip

Read zip files/buffers

IO::Zlib

IO:: style interface to Compress::Zlib

IPC::Cmd

Finding and running system commands made easy

IPC::Msg

SysV Msg IPC object class

IPC::Open2

Open a process for both reading and writing using open2()

IPC::Open3

Open a process for reading, writing, and error handling using open3()

IPC::Semaphore

SysV Semaphore IPC object class

IPC::SharedMem

SysV Shared Memory IPC object class

IPC::SysV

System V IPC constants and system calls

Internals

Reserved special namespace for internals related functions

JSON::PP

JSON::XS compatible pure-Perl module.

JSON::PP::Boolean

Dummy module providing JSON::PP::Boolean

List::Util

A selection of general-utility list subroutines

List::Util::XS

Indicate if List::Util was compiled with a C compiler

Locale::Maketext

Framework for localization

Locale::Maketext::Cookbook

Recipes for using Locale::Maketext

Locale::Maketext::Guts

Deprecated module to load Locale::Maketext utf8 code

Locale::Maketext::GutsLoader

Deprecated module to load Locale::Maketext utf8 code

Locale::Maketext::Simple

Simple interface to Locale::Maketext::Lexicon

Locale::Maketext::TPJ13

Article about software localization

MIME::Base64

Encoding and decoding of base64 strings

MIME::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::BigInt::FastCalc

Math::BigInt::Calc with some XS for more speed

Math::BigInt::Lib

Virtual parent class for Math::BigInt libraries

Math::BigRat

Arbitrary size rational number math package

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::NDBM_File

Glue to provide EXISTS for NDBM_File for Storable use

Memoize::SDBM_File

DEPRECATED compability shim

Memoize::Storable

Store Memoized data in Storable database

Module::CoreList

What modules shipped with versions of perl

Module::CoreList::Utils

What utilities shipped with versions of perl

Module::Load

Runtime require of both modules and files

Module::Load::Conditional

Looking up module information / loading at runtime

Module::Loaded

Mark modules as loaded or unloaded

Module::Metadata

Gather package and POD information from perl module files

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::FTP::dataconn

FTP Client data connection 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

Params::Check

A generic input parsing/checking mechanism.

Parse::CPAN::Meta

Parse META.yml and META.json CPAN metadata files

Perl::OSType

Map Perl operating system names to generic types

PerlIO

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

PerlIO::encoding

Encoding layer

PerlIO::mmap

Memory mapped IO

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::Escapes

For resolving Pod E<...> sequences

Pod::Functions

Group Perl's functions a la perlfunc.pod

Pod::Html

Module to convert pod files to HTML

Pod::Html::Util

Helper functions for Pod-Html

Pod::Man

Convert POD data to formatted *roff input

Pod::ParseLink

Parse an L<> formatting code in POD text

Pod::Perldoc

Look up Perl documentation in Pod format.

Pod::Perldoc::BaseTo

Base for Pod::Perldoc formatters

Pod::Perldoc::GetOptsOO

Customized option parser for Pod::Perldoc

Pod::Perldoc::ToANSI

Render Pod with ANSI color escapes

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::ToTerm

Render Pod with terminal escapes

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::Simple

Framework for parsing Pod

Pod::Simple::Checker

Check the Pod syntax of a document

Pod::Simple::Debug

Put Pod::Simple into trace/debug mode

Pod::Simple::DumpAsText

Dump Pod-parsing events as text

Pod::Simple::DumpAsXML

Turn Pod into XML

Pod::Simple::HTML

Convert Pod to HTML

Pod::Simple::HTMLBatch

Convert several Pod files to several HTML files

Pod::Simple::JustPod

Just the Pod, the whole Pod, and nothing but the Pod

Pod::Simple::LinkSection

Represent "section" attributes of L codes

Pod::Simple::Methody

Turn Pod::Simple events into method calls

Pod::Simple::PullParser

A pull-parser interface to parsing Pod

Pod::Simple::PullParserEndToken

End-tokens from Pod::Simple::PullParser

Pod::Simple::PullParserStartToken

Start-tokens from Pod::Simple::PullParser

Pod::Simple::PullParserTextToken

Text-tokens from Pod::Simple::PullParser

Pod::Simple::PullParserToken

Tokens from Pod::Simple::PullParser

Pod::Simple::RTF

Format Pod as RTF

Pod::Simple::Search

Find POD documents in directory trees

Pod::Simple::SimpleTree

Parse Pod into a simple parse tree

Pod::Simple::Subclassing

Write a formatter as a Pod::Simple subclass

Pod::Simple::Text

Format Pod as plaintext

Pod::Simple::TextContent

Get the text content of Pod

Pod::Simple::XHTML

Format Pod as validating XHTML

Pod::Simple::XMLOutStream

Turn Pod into XML

Pod::Text

Convert POD data to formatted 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

Extracts POD documentation and shows usage information

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

Look - search for key in dictionary file

SelectSaver

Save and restore selected file handle

SelfLoader

Load functions only on demand

Storable

Persistence for Perl data structures

Sub::Util

A selection of utility subroutines for subs and CODE references

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

Sys::Syslog::Win32

Win32 support for Sys::Syslog

TAP::Base

Base class that provides common functionality to TAP::Parser

TAP::Formatter::Base

Base class for harness output delegates

TAP::Formatter::Color

Run Perl test scripts with color

TAP::Formatter::Console

Harness output delegate for default console output

TAP::Formatter::Console::ParallelSession

Harness output delegate for parallel console output

TAP::Formatter::Console::Session

Harness output delegate for default console output

TAP::Formatter::File

Harness output delegate for file output

TAP::Formatter::File::Session

Harness output delegate for file output

TAP::Formatter::Session

Abstract base class for harness output delegate

TAP::Harness

Run test scripts with statistics

TAP::Harness::Env

Parsing harness related environmental variables where appropriate

TAP::Object

Base class that provides common functionality to all TAP::* modules

TAP::Parser

Parse TAP output

TAP::Parser::Aggregator

Aggregate TAP::Parser results

TAP::Parser::Grammar

A grammar for the Test Anything Protocol.

TAP::Parser::Iterator

Base class for TAP source iterators

TAP::Parser::Iterator::Array

Iterator for array-based TAP sources

TAP::Parser::Iterator::Process

Iterator for process-based TAP sources

TAP::Parser::Iterator::Stream

Iterator for filehandle-based TAP sources

TAP::Parser::IteratorFactory

Figures out which SourceHandler objects to use for a given Source

TAP::Parser::Multiplexer

Multiplex multiple TAP::Parsers

TAP::Parser::Result

Base class for TAP::Parser output objects

TAP::Parser::Result::Bailout

Bailout result token.

TAP::Parser::Result::Comment

Comment result token.

TAP::Parser::Result::Plan

Plan result token.

TAP::Parser::Result::Pragma

TAP pragma token.

TAP::Parser::Result::Test

Test result token.

TAP::Parser::Result::Unknown

Unknown result token.

TAP::Parser::Result::Version

TAP syntax version token.

TAP::Parser::Result::YAML

YAML result token.

TAP::Parser::ResultFactory

Factory for creating TAP::Parser output objects

TAP::Parser::Scheduler

Schedule tests during parallel testing

TAP::Parser::Scheduler::Job

A single testing job.

TAP::Parser::Scheduler::Spinner

A no-op job.

TAP::Parser::Source

A TAP source & meta data about it

TAP::Parser::SourceHandler

Base class for different TAP source handlers

TAP::Parser::SourceHandler::Executable

Stream output from an executable TAP source

TAP::Parser::SourceHandler::File

Stream TAP from a text file.

TAP::Parser::SourceHandler::Handle

Stream TAP from an IO::Handle or a GLOB.

TAP::Parser::SourceHandler::Perl

Stream TAP from a Perl executable

TAP::Parser::SourceHandler::RawTAP

Stream output from raw TAP in a scalar/array ref.

TAP::Parser::YAMLish::Reader

Read YAMLish data from iterator

TAP::Parser::YAMLish::Writer

Write YAMLish data

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 various readline packages.

Term::Table

Format a header and rows into a table

Term::Table::Cell

Representation of a cell in a table.

Term::Table::CellStack

Combine several cells into one (vertical)

Term::Table::HashBase

Build hash based classes.

Term::Table::LineBreak

Break up lines for use in tables.

Term::Table::Util

Utilities for Term::Table.

Test

Provides a simple framework for writing test scripts

Test2

Framework for writing test tools that all work together.

Test2::API

Primary interface for writing Test2 based testing tools.

Test2::API::Breakage

What breaks at what version

Test2::API::Context

Object to represent a testing context.

Test2::API::Instance

Object used by Test2::API under the hood

Test2::API::InterceptResult

Representation of a list of events.

Test2::API::InterceptResult::Event

Representation of an event for use in

Test2::API::InterceptResult::Hub

Hub used by InterceptResult.

Test2::API::InterceptResult::Squasher

Encapsulation of the algorithm that

Test2::API::Stack

Object to manage a stack of Test2::Hub

Test2::AsyncSubtest

Object representing an async subtest.

Test2::AsyncSubtest::Event::Attach

Event to attach a subtest to the parent.

Test2::AsyncSubtest::Event::Detach

Event to detach a subtest from the parent.

Test2::AsyncSubtest::Hub

Hub used by async subtests.

Test2::Bundle

Documentation for bundles.

Test2::Bundle::Extended

Old name for Test2::V0

Test2::Bundle::More

ALMOST a drop-in replacement for Test::More.

Test2::Bundle::Simple

ALMOST a drop-in replacement for Test::Simple.

Test2::Compare

Test2 extension for writing deep comparison tools.

Test2::Compare::Array

Internal representation of an array comparison.

Test2::Compare::Bag

Internal representation of a bag comparison.

Test2::Compare::Base

Base class for comparison classes.

Test2::Compare::Bool

Compare two values as booleans

Test2::Compare::Custom

Custom field check for comparisons.

Test2::Compare::DeepRef

Ref comparison

Test2::Compare::Delta

Representation of differences between nested data

Test2::Compare::Event

Event specific Object subclass.

Test2::Compare::EventMeta

Meta class for events in deep comparisons

Test2::Compare::Float

Compare two values as numbers with tolerance.

Test2::Compare::Hash

Representation of a hash in a deep comparison.

Test2::Compare::Isa

Check if the value is an instance of the class.

Test2::Compare::Meta

Check library for meta-checks

Test2::Compare::Negatable

Poor mans 'role' for compare objects that can be negated.

Test2::Compare::Number

Compare two values as numbers

Test2::Compare::Object

Representation of an object during deep

Test2::Compare::OrderedSubset

Internal representation of an ordered subset.

Test2::Compare::Pattern

Use a pattern to validate values in a deep

Test2::Compare::Ref

Ref comparison

Test2::Compare::Regex

Regex direct comparison

Test2::Compare::Scalar

Representation of a Scalar Ref in deep

Test2::Compare::Set

Allows a field to be matched against a set of

Test2::Compare::String

Compare two values as strings

Test2::Compare::Undef

Check that something is undefined

Test2::Compare::Wildcard

Placeholder check.

Test2::Event

Base class for events

Test2::Event::Bail

Bailout!

Test2::Event::Diag

Diag event type

Test2::Event::Encoding

Set the encoding for the output stream

Test2::Event::Exception

Exception event

Test2::Event::Fail

Event for a simple failed assertion

Test2::Event::Generic

Generic event type.

Test2::Event::Note

Note event type

Test2::Event::Ok

Ok event type

Test2::Event::Pass

Event for a simple passing assertion

Test2::Event::Plan

The event of a plan

Test2::Event::Skip

Skip event type

Test2::Event::Subtest

Event for subtest types

Test2::Event::TAP::Version

Event for TAP version.

Test2::Event::V2

Second generation event.

Test2::Event::Waiting

Tell all procs/threads it is time to be done

Test2::EventFacet

Base class for all event facets.

Test2::EventFacet::About

Facet with event details.

Test2::EventFacet::Amnesty

Facet for assertion amnesty.

Test2::EventFacet::Assert

Facet representing an assertion.

Test2::EventFacet::Control

Facet for hub actions and behaviors.

Test2::EventFacet::Error

Facet for errors that need to be shown.

Test2::EventFacet::Hub

Facet for the hubs an event passes through.

Test2::EventFacet::Info

Facet for information a developer might care about.

Test2::EventFacet::Info::Table

Intermediary representation of a table.

Test2::EventFacet::Meta

Facet for meta-data

Test2::EventFacet::Parent

Facet for events contains other events

Test2::EventFacet::Plan

Facet for setting the plan

Test2::EventFacet::Render

Facet that dictates how to render an event.

Test2::EventFacet::Trace

Debug information for events

Test2::Formatter

Namespace for formatters.

Test2::Formatter::TAP

Standard TAP formatter

Test2::Hub

The conduit through which all events flow.

Test2::Hub::Interceptor

Hub used by interceptor to grab results.

Test2::Hub::Interceptor::Terminator

Exception class used by

Test2::Hub::Subtest

Hub used by subtests

Test2::IPC

Turn on IPC for threading or forking support.

Test2::IPC::Driver

Base class for Test2 IPC drivers.

Test2::IPC::Driver::Files

Temp dir + Files concurrency model.

Test2::Manual

Documentation hub for Test2 and Test2-Suite.

Test2::Manual::Anatomy

The hub for documentation of the inner workings of

Test2::Manual::Anatomy::API

Internals documentation for the API.

Test2::Manual::Anatomy::Context

Internals documentation for the Context

Test2::Manual::Anatomy::Event

The internals of events

Test2::Manual::Anatomy::Hubs

Internals documentation for the hub stack, and

Test2::Manual::Anatomy::IPC

Manual for the IPC system.

Test2::Manual::Anatomy::Utilities

Overview of utilities for Test2.

Test2::Manual::Concurrency

Documentation for Concurrency support.

Test2::Manual::Contributing

How to contribute to the Test2 project.

Test2::Manual::EndToEnd

Overview of Test2 from load to finish.

Test2::Manual::Testing

Hub for documentation about writing tests with Test2.

Test2::Manual::Testing::Introduction

Introduction to testing with Test2.

Test2::Manual::Testing::Migrating

How to migrate existing tests from

Test2::Manual::Testing::Planning

The many ways to set a plan.

Test2::Manual::Testing::Todo

Tutorial for marking tests as TODO.

Test2::Manual::Tooling

Manual page for tool authors.

Test2::Manual::Tooling::FirstTool

Write your first tool with Test2.

Test2::Manual::Tooling::Formatter

How to write a custom formatter, in our

Test2::Manual::Tooling::Nesting

Tutorial for using other tools within your

Test2::Manual::Tooling::Plugin::TestExit

How to safely add pre-exit

Test2::Manual::Tooling::Plugin::TestingDone

Run code when the test file is

Test2::Manual::Tooling::Plugin::ToolCompletes

How to add behaviors that occur

Test2::Manual::Tooling::Plugin::ToolStarts

How to add behaviors that occur

Test2::Manual::Tooling::Subtest

How to implement a tool that makes use of

Test2::Manual::Tooling::TestBuilder

This section maps Test::Builder methods

Test2::Manual::Tooling::Testing

Tutorial on how to test your testing tools.

Test2::Mock

Module for managing mocked classes and instances.

Test2::Plugin

Documentation for plugins

Test2::Plugin::BailOnFail

Automatically bail out of testing on the first test

Test2::Plugin::DieOnFail

Automatically die on the first test failure.

Test2::Plugin::ExitSummary

Add extra diagnostics on failure at the end of the

Test2::Plugin::SRand

Control the random seed for more controlled test

Test2::Plugin::Times

Output timing data at the end of the test.

Test2::Plugin::UTF8

Test2 plugin to test with utf8.

Test2::Require

Base class and documentation for skip-unless type test

Test2::Require::AuthorTesting

Only run a test when the AUTHOR_TESTING

Test2::Require::AutomatedTesting

Only run a test when the AUTOMATED_TESTING

Test2::Require::EnvVar

Only run a test when a specific environment variable

Test2::Require::ExtendedTesting

Only run a test when the EXTENDED_TESTING

Test2::Require::Fork

Skip a test file unless the system supports forking

Test2::Require::Module

Skip tests if certain packages are not installed, or

Test2::Require::NonInteractiveTesting

Only run a test when the NONINTERACTIVE_TESTING

Test2::Require::Perl

Skip the test unless the necessary version of Perl is

Test2::Require::RealFork

Skip a test file unless the system supports true

Test2::Require::ReleaseTesting

Only run a test when the RELEASE_TESTING

Test2::Require::Threads

Skip a test file unless the system supports threading

Test2::Suite

Distribution with a rich set of tools built upon the Test2

Test2::Todo

TODO extension for Test2.

Test2::Tools

Documentation for Tools.

Test2::Tools::AsyncSubtest

Tools for writing async subtests.

Test2::Tools::Basic

Test2 implementation of the basic testing tools.

Test2::Tools::Class

Test2 implementation of the tools for testing classes.

Test2::Tools::ClassicCompare

Classic (Test::More style) comparison tools.

Test2::Tools::Compare

Tools for comparing deep data structures.

Test2::Tools::Defer

Write tests that get executed at a later time

Test2::Tools::Encoding

Tools for managing the encoding of Test2 based

Test2::Tools::Event

Tools for generating test events.

Test2::Tools::Exception

Test2 based tools for checking exceptions

Test2::Tools::Exports

Tools for validating exporters.

Test2::Tools::GenTemp

Tool for generating a populated temp directory.

Test2::Tools::Grab

Temporarily intercept all events without adding a scope

Test2::Tools::Mock

Class/Instance mocking for Test2.

Test2::Tools::Ref

Tools for validating references.

Test2::Tools::Spec

RSPEC implementation on top of Test2::Workflow

Test2::Tools::Subtest

Tools for writing subtests

Test2::Tools::Target

Alias the testing target package.

Test2::Tools::Tester

Tools to help you test other testing tools.

Test2::Tools::Tiny

Tiny set of tools for unfortunate souls who cannot use

Test2::Tools::Warnings

Tools to verify warnings.

Test2::Transition

Transition notes when upgrading to Test2

Test2::Util

Tools used by Test2 and friends.

Test2::Util::ExternalMeta

Allow third party tools to safely attach meta-data

Test2::Util::Facets2Legacy

Convert facet data to the legacy event API.

Test2::Util::Grabber

Object used to temporarily intercept all events.

Test2::Util::Guard

Inline copy of Scope::Guard

Test2::Util::HashBase

Build hash based classes.

Test2::Util::Importer

Inline copy of Importer.

Test2::Util::Ref

Tools for inspecting or manipulating references.

Test2::Util::Stash

Utilities for manipulating stashes and globs.

Test2::Util::Sub

Tools for inspecting and manipulating subs.

Test2::Util::Table

Format a header and rows into a table

Test2::Util::Table::LineBreak

Break up lines for use in tables.

Test2::Util::Times

Format timing/benchmark information.

Test2::Util::Trace

Legacy wrapper fro Test2::EventFacet::Trace.

Test2::V0

0Th edition of the Test2 recommended bundle.

Test2::Workflow

A test workflow is a way of structuring tests using

Test2::Workflow::BlockBase

Base class for all workflow blocks.

Test2::Workflow::Build

Represents a build in progress.

Test2::Workflow::Runner

Runs the workflows.

Test2::Workflow::Task

Encapsulation of a Task

Test2::Workflow::Task::Action

Encapsulation of an action.

Test2::Workflow::Task::Group

Encapsulation of a group (describe).

Test::Builder

Backend for building test libraries

Test::Builder::Formatter

Test::Builder subclass of Test2::Formatter::TAP

Test::Builder::IO::Scalar

A copy of IO::Scalar for Test::Builder

Test::Builder::Module

Base class for test modules

Test::Builder::Tester

Test testsuites that have been built with

Test::Builder::Tester::Color

Turn on colour in Test::Builder::Tester

Test::Builder::TodoDiag

Test::Builder subclass of Test2::Event::Diag

Test::Harness

Run Perl standard test scripts with statistics

Test::Harness::Beyond

Beyond make test

Test::More

Yet another framework for writing test scripts

Test::Simple

Basic utilities for writing tests.

Test::Tester

Ease testing test modules built with Test::Builder

Test::Tester::Capture

Help testing test modules built with Test::Builder

Test::Tester::CaptureRunner

Help testing test modules built with Test::Builder

Test::Tutorial

A tutorial about writing really basic tests

Test::use::ok

Alternative to Test::More::use_ok

Text::Abbrev

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::Tabs

Expand and unexpand tabs like 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

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::Hash::NamedCapture

Named regexp capture buffers

Tie::Memoize

Add data to hash when needed

Tie::RefHash

Use references as hash keys

Tie::Scalar

Base class definitions for tied scalars

Tie::StdHandle

Base class definitions for tied handles

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::Piece

Object Oriented time objects

Time::Seconds

A simple API to convert seconds to other date values

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::Collate::CJK::Big5

Weighting CJK Unified Ideographs

Unicode::Collate::CJK::GB2312

Weighting CJK Unified Ideographs

Unicode::Collate::CJK::JISX0208

Weighting JIS KANJI for Unicode::Collate

Unicode::Collate::CJK::Korean

Weighting CJK Unified Ideographs

Unicode::Collate::CJK::Pinyin

Weighting CJK Unified Ideographs

Unicode::Collate::CJK::Stroke

Weighting CJK Unified Ideographs

Unicode::Collate::CJK::Zhuyin

Weighting CJK Unified Ideographs

Unicode::Collate::Locale

Linguistic tailoring for DUCET via Unicode::Collate

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

VMS::DCLsym

Perl extension to manipulate DCL symbols

VMS::Filespec

Convert between VMS and Unix file specification syntax

VMS::Stdio

Standard I/O functions via VMS extensions

Win32

Interfaces to some Win32 API Functions

Win32API::File

Low-level access to Win32 system API calls for files/dirs.

Win32CORE

Win32 CORE function stubs

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

autodie::Scope::Guard

Wrapper class for calling subs at end of scope

autodie::Scope::GuardStack

Hook stack for managing scopes via %^H

autodie::Util

Internal Utility subroutines for autodie and Fatal

version::Internals

Perl extension for Version Objects

To find out all modules installed on your system, including those without documentation or outside the standard release, just use the following command (under the default win32 shell, double quotes should be used instead of single quotes).

    % perl -MFile::Find=find -MFile::Spec::Functions -Tlwe \
      'find { wanted => sub { print canonpath $_ if /\.pm\z/ },
      no_chdir => 1 }, @INC'

(The -T is here to prevent @INC from being populated by PERL5LIB, PERLLIB, and PERL_USE_UNSAFE_INC.) They should all have their own documentation installed and accessible via your system man(1) command.  If you do not have a find program, you can use the Perl find2perl program instead, which generates Perl code as output you can run through perl.  If you have a man program but it doesn't find your modules, you'll have to fix your manpath.  See perl for details.  If you have no system man command, you might try the perldoc program.

Note also that the command perldoc perllocal gives you a (possibly incomplete) list of the modules that have been further installed on your system. (The perllocal.pod file is updated by the standard MakeMaker install process.)

Extension modules are written in C (or a mix of Perl and C).  They are usually dynamically loaded into Perl if and when you need them, but may also be linked in statically.  Supported extension modules include Socket, Fcntl, and POSIX.

Many popular C extension modules do not come bundled (at least, not completely) due to their sizes, volatility, or simply lack of time for adequate testing and configuration across the multitude of platforms on which Perl was beta-tested.  You are encouraged to look for them on CPAN (described below), or using web search engines like Google or DuckDuckGo.

• Do similar modules already exist in some form?

  If so, please try to reuse the existing modules either in whole or by inheriting useful features into a new class.  If this is not practical try to get together with the module authors to work on extending or enhancing the functionality of the existing modules. A perfect example is the plethora of packages in perl4 for dealing with command line options.

  If you are writing a module to expand an already existing set of modules, please coordinate with the author of the package.  It helps if you follow the same naming scheme and module interaction scheme as the original author.

• Try to design the new module to be easy to extend and reuse.

  Try to use warnings; (or use warnings qw(...);). Remember that you can add no warnings qw(...); to individual blocks of code that need less warnings.

  Use blessed references.  Use the two argument form of bless to bless into the class name given as the first parameter of the constructor, e.g.,:

   sub new {
       my $class = shift;
       return bless {}, $class;
   }

  or even this if you'd like it to be used as either a static or a virtual method.

   sub new {
       my $self  = shift;
       my $class = ref($self) || $self;
       return bless {}, $class;
   }

  Pass arrays as references so more parameters can be added later (it's also faster).  Convert functions into methods where appropriate.  Split large methods into smaller more flexible ones. Inherit methods from other modules if appropriate.

  Avoid class name tests like: die "Invalid" unless ref $ref eq 'FOO'. Generally you can delete the eq 'FOO' part with no harm at all. Let the objects look after themselves! Generally, avoid hard-wired class names as far as possible.

  Avoid $r->Class::func() where using @ISA=qw(... Class ...) and $r->func() would work.

  Use autosplit so little used or newly added functions won't be a burden to programs that don't use them. Add test functions to the module after __END__ either using AutoSplit or by saying:

   eval join('',<main::DATA>) || die $@ unless caller();

  Does your module pass the 'empty subclass' test? If you say @SUBCLASS::ISA = qw(YOURCLASS); your applications should be able to use SUBCLASS in exactly the same way as YOURCLASS.  For example, does your application still work if you change:  $obj = YOURCLASS->new(); into: $obj = SUBCLASS->new(); ?

  Avoid keeping any state information in your packages. It makes it difficult for multiple other packages to use yours. Keep state information in objects.

  Always use -w.

  Try to use strict; (or use strict qw(...);). Remember that you can add no strict qw(...); to individual blocks of code that need less strictness.

  Always use -w.

  Follow the guidelines in perlstyle.

  Always use -w.

• Some simple style guidelines

  The perlstyle manual supplied with Perl has many helpful points.

  Coding style is a matter of personal taste. Many people evolve their style over several years as they learn what helps them write and maintain good code.  Here's one set of assorted suggestions that seem to be widely used by experienced developers:

  Use underscores to separate words.  It is generally easier to read $var_names_like_this than $VarNamesLikeThis, especially for non-native speakers of English. It's also a simple rule that works consistently with VAR_NAMES_LIKE_THIS.

  Package/Module names are an exception to this rule. Perl informally reserves lowercase module names for 'pragma' modules like integer and strict. Other modules normally begin with a capital letter and use mixed case with no underscores (need to be short and portable).

  You may find it helpful to use letter case to indicate the scope or nature of a variable. For example:

   $ALL_CAPS_HERE   constants only (beware clashes with Perl vars)
   $Some_Caps_Here  package-wide global/static
   $no_caps_here    function scope my() or local() variables

  Function and method names seem to work best as all lowercase. e.g., $obj->as_string().

  You can use a leading underscore to indicate that a variable or function should not be used outside the package that defined it.

• Select what to export.

  Do NOT export method names!

  Do NOT export anything else by default without a good reason!

  Exports pollute the namespace of the module user.  If you must export try to use @EXPORT_OK in preference to @EXPORT and avoid short or common names to reduce the risk of name clashes.

  Generally anything not exported is still accessible from outside the module using the ModuleName::item_name (or $blessed_ref->method) syntax.  By convention you can use a leading underscore on names to indicate informally that they are 'internal' and not for public use.

  (It is actually possible to get private functions by saying: my $subref = sub { ... };  &$subref;.  But there's no way to call that directly as a method, because a method must have a name in the symbol table.)

  As a general rule, if the module is trying to be object oriented then export nothing. If it's just a collection of functions then @EXPORT_OK anything but use @EXPORT with caution.

• Select a name for the module.

  This name should be as descriptive, accurate, and complete as possible.  Avoid any risk of ambiguity. Always try to use two or more whole words.  Generally the name should reflect what is special about what the module does rather than how it does it.  Please use nested module names to group informally or categorize a module. There should be a very good reason for a module not to have a nested name. Module names should begin with a capital letter.

  Having 57 modules all called Sort will not make life easy for anyone (though having 23 called Sort::Quick is only marginally better :-). Imagine someone trying to install your module alongside many others.

  If you are developing a suite of related modules/classes it's good practice to use nested classes with a common prefix as this will avoid namespace clashes. For example: Xyz::Control, Xyz::View, Xyz::Model etc. Use the modules in this list as a naming guide.

  If adding a new module to a set, follow the original author's standards for naming modules and the interface to methods in those modules.

  If developing modules for private internal or project specific use, that will never be released to the public, then you should ensure that their names will not clash with any future public module. You can do this either by using the reserved Local::* category or by using a category name that includes an underscore like Foo_Corp::*.

  To be portable each component of a module name should be limited to 11 characters. If it might be used on MS-DOS then try to ensure each is unique in the first 8 characters. Nested modules make this easier.

  For additional guidance on the naming of modules, please consult:

      https://pause.perl.org/pause/query?ACTION=pause_namingmodules

  or send mail to the <module-authors@perl.org> mailing list.

• Have you got it right?

  How do you know that you've made the right decisions? Have you picked an interface design that will cause problems later? Have you picked the most appropriate name? Do you have any questions?

  The best way to know for sure, and pick up many helpful suggestions, is to ask someone who knows. The <module-authors@perl.org> mailing list is useful for this purpose; it's also accessible via news interface as perl.module-authors at nntp.perl.org.

  All you need to do is post a short summary of the module, its purpose and interfaces. A few lines on each of the main methods is probably enough. (If you post the whole module it might be ignored by busy people - generally the very people you want to read it!)

  Don't worry about posting if you can't say when the module will be ready - just say so in the message. It might be worth inviting others to help you, they may be able to complete it for you!

• README and other Additional Files.

  It's well known that software developers usually fully document the software they write. If, however, the world is in urgent need of your software and there is not enough time to write the full documentation please at least provide a README file containing:

  • A description of the module/package/extension etc.
  • A copyright notice - see below.
  • Prerequisites - what else you may need to have.
  • How to build it - possible changes to Makefile.PL etc.
  • How to install it.
  • Recent changes in this release, especially incompatibilities
  • Changes / enhancements you plan to make in the future.

  If the README file seems to be getting too large you may wish to split out some of the sections into separate files: INSTALL, Copying, ToDo etc.

  • Adding a Copyright Notice.

    How you choose to license your work is a personal decision. The general mechanism is to assert your Copyright and then make a declaration of how others may copy/use/modify your work.

    Perl, for example, is supplied with two types of licence: The GNU GPL and The Artistic Licence (see the files README, Copying, and Artistic, or perlgpl and perlartistic).  Larry has good reasons for NOT just using the GNU GPL.

    My personal recommendation, out of respect for Larry, Perl, and the Perl community at large is to state something simply like:

     Copyright (c) 1995 Your Name. All rights reserved.
     This program is free software; you can redistribute it and/or
     modify it under the same terms as Perl itself.

    This statement should at least appear in the README file. You may also wish to include it in a Copying file and your source files. Remember to include the other words in addition to the Copyright.

  • Give the module a version/issue/release number.

    To be fully compatible with the Exporter and MakeMaker modules you should store your module's version number in a non-my package variable called $VERSION.  This should be a positive floating point number with at least two digits after the decimal (i.e., hundredths, e.g, $VERSION = "0.01").  Don't use a "1.3.2" style version. See Exporter for details.

    It may be handy to add a function or method to retrieve the number. Use the number in announcements and archive file names when releasing the module (ModuleName-1.02.tar.Z). See perldoc ExtUtils::MakeMaker.pm for details.

  • How to release and distribute a module.

    If possible, register the module with CPAN. Follow the instructions and links on:

       https://www.cpan.org/modules/04pause.html

    and upload to:

       https://pause.perl.org/

    and notify <modules@perl.org>. This will allow anyone to install your module using the cpan tool distributed with Perl.

    By using the WWW interface you can ask the Upload Server to mirror your modules from your ftp or WWW site into your own directory on CPAN!

  • Take care when changing a released module.

    Always strive to remain compatible with previous released versions. Otherwise try to add a mechanism to revert to the old behavior if people rely on it.  Document incompatible changes.

• There is no requirement to convert anything.

  If it ain't broke, don't fix it! Perl 4 library scripts should continue to work with no problems. You may need to make some minor changes (like escaping non-array @'s in double quoted strings) but there is no need to convert a .pl file into a Module for just that.

• Consider the implications.

  All Perl applications that make use of the script will need to be changed (slightly) if the script is converted into a module.  Is it worth it unless you plan to make other changes at the same time?

• Make the most of the opportunity.

  If you are going to convert the script to a module you can use the opportunity to redesign the interface.  The guidelines for module creation above include many of the issues you should consider.

• The pl2pm utility will get you started.

  This utility will read *.pl files (given as parameters) and write corresponding *.pm files. The pl2pm utilities does the following:

  • Adds the standard Module prologue lines
  • Converts package specifiers from ' to ::
  • Converts die(...) to croak(...)
  • Several other minor changes

  Being a mechanical process pl2pm is not bullet proof. The converted code will need careful checking, especially any package statements. Don't delete the original .pl file till the new .pm one works!

• Complete applications rarely belong in the Perl Module Library.

• Many applications contain some Perl code that could be reused.

  Help save the world! Share your code in a form that makes it easy to reuse.

• Break-out the reusable code into one or more separate module files.
• Take the opportunity to reconsider and redesign the interfaces.

• In some cases the 'application' can then be reduced to a small

  fragment of code built on top of the reusable modules. In these cases the application could invoked as:

       % perl -e 'use Module::Name; method(@ARGV)' ...
  or
       % perl -mModule::Name ...    (in perl5.002 or higher)