Devel::Cycle This is a tool for finding circular references in objects and other types of references. Because of Perl's reference-count based memory management, circular references will cause memory leaks.

This module understands the ICal date/time and duration formats, as defined in RFC 2445. It can be used to parse these formats in order to create the appropriate objects.

PPI::XS provides (minor) XS acceleration for PPI.

This module provide functions that takes a list of values as their argument and produces a string as its result. The string contains Perl code that, when "eval"ed, produces a deep copy of the original arguments.

This module provides a small, fast utility for working with file paths.

This package provides an ASCII mapping for the eucJP encoding.

This Perl library provides a function which tells whether a specific time falls within a specified time period. Its syntax for specifying time periods allows you to test for conditions like "Monday to Friday, 9am till 5pm" and "on the second Tuesday of the month" and "between 4pm and 4:15pm" and "in the first half of each minute" and "in January of 1998".

The Cache modules are designed to assist a developer in persisting data for a specified period of time. Often these modules are used in web applications to store data locally to save repeated and redundant expensive calls to remote machines or databases. People have also been known to use Cache::Cache for its straightforward interface in sharing data between runs of an application or invocations of a CGI-style script or simply as an easy to use abstraction of the file system or shared memory.

This package provides functions to work with directory and file names.

Statistics::Distributions calculates percentage points (5 significant digits) of the u (standard normal) distribution, the student's t distribution, the chi-square distribution and the F distribution. It can also calculate the upper probability (5 significant digits) of the u (standard normal), the chi-square, the t and the F distribution.

Crypt::UnixCrypt_XS implements the DES-based Unix crypt function. For those who need to construct non-standard variants of crypt, the various building blocks used in crypt are also supplied separately.

This class provides several methods for host name resolution. It is designed to be used with event loops. Names are resolved by your system's native getaddrinfo(3) implementation, called in a separate thread to avoid blocking the entire application. Threading overhead is limited by using system threads instead of Perl threads.

The Digest::CRC module calculates CRC sums of all sorts. It contains wrapper functions with the correct parameters for CRC-CCITT, CRC-16 and CRC-32.

Text::ParseWords module is used to parse text into an array of tokens or array of arrays.

Crypt::DES is an XS-based implementation of the DES cryptography algorithm. The module implements the Crypt::CBC interface which has blocksize, keysize, encrypt and decrypt functions.

YAML::Tiny is a perl class for reading and writing YAML-style files, written with as little code as possible, reducing load time and memory overhead.

Socket::MsgHdr provides advanced socket messaging operations via sendmsg and recvmsg.

It also allows manipulating ancillary data or so-called control information (cmsghdr). This ancillary data may be used for file descriptor passing, IPv6 operations, and a host of implementation-specific extensions.

This module provides syntactical support for try/catch control flows.

This module allows you to execute code when perl finished compiling the surrounding scope.

This module splits a set of data with IDs and arbitrary values into one test file per (key+value) for easy parallelisation.

When subclassing a class, you may occasionally want to dispatch control to the superclass---at least conditionally and temporarily. This module provides nicer equivalents to the native Perl syntax for calling superclasses, along with a universal super method to determine a class' own superclass, and better support for run-time mix-ins and roles.

Async::Interrupt implements a single feature only of interest to advanced perl modules, namely asynchronous interruptions (think "UNIX signals", which are very similar).

Sometimes, modules wish to run code asynchronously (in another thread, or from a signal handler), and then signal the perl interpreter on certain events. One common way is to write some data to a pipe and use an event handling toolkit to watch for I/O events. Another way is to send a signal. Those methods are slow, and in the case of a pipe, also not asynchronous - it won't interrupt a running perl interpreter.

This module implements asynchronous notifications that enable you to signal running perl code from another thread, asynchronously, and sometimes even without using a single syscall.

This module exports a single function: ttie. It ties a variable to a type constraint, ensuring that whatever values stored in the variable will conform to the type constraint. If the type constraint has coercions, these will be used if necessary to ensure values assigned to the variable conform.

Strictures turns on strict and make all warnings fatal when run from within a source-controlled directory.