File locking in Perl is usually done using the flock function. Unfortunately, this only allows locks on whole files and is often implemented in terms of the flock(2) system function which has some shortcomings (especially concerning locks on remotely mounted file systems) and slightly different behaviour than fcntl(2).

Moose is a complete object system for Perl 5. It provides keywords for attribute declaration, object construction, inheritance, and maybe more. With Moose, you define your class declaratively, without needing to know about blessed hashrefs, accessor methods, and so on. You can concentrate on the logical structure of your classes, focusing on "what" rather than "how". A class definition with Moose reads like a list of very concise English sentences.

The Digest::MD4 module allows you to use the RSA Data Security Inc.: MD4 Message Digest algorithm from within Perl programs. The algorithm takes as input a message of arbitrary length and produces as output a 128-bit "fingerprint" or "message digest" of the input. MD4 is described in RFC 1320.

This module is intended to easily load initialization values for attributes on object construction from an appropriate config file. The building is done in MooX::ConfigFromFile::Role---using MooX::ConfigFromFile ensures that the role is applied.

Mail::RFC822::Address validates email addresses against the grammar described in RFC 822 using regular expressions.

This module in a fully object-oriented implementation of a simple n-ary tree.

This module allows one to run a subset of the subtest tests given in a test file.

The module declaration takes a whitelist of the subtests we want to run. Any subtest that doesn't match any of the whitelist items will be skipped (or potentially bypassed).

Sys::Syscall allows one to use epoll and sendfile system calls from Perl. Support is mostly Linux-only for now, but other syscalls/OSes are planned for the future.

Indirect warns about using the indirect method call syntax.

This module converts Perl data structures to JSON and vice versa.

Perl module for using special zip files (called Perl ARchives) as libraries from which Perl modules can be loaded.

MooseX::MarkAsMethods allows one to easily mark certain functions as Moose methods. This will allow other packages such as namespace::autoclean to operate without blowing away your overloads. After using MooseX::MarkAsMethods your overloads will be recognized by Class::MOP as being methods, and class extension as well as composition from roles with overloads will "just work".

CPAN::DistnameInfo uses heuristics to extract the distribution name and version from filenames.

Provides several perl modules for date/time manipulation: Time::CTime.pm, Time::JulianDay.pm, Time::ParseDate.pm, Time::Timezone.pm, and Time::DaysInMonth.pm.

This module creates a customized, highly efficient parameter checking subroutine. It can handle named or positional parameters, and can return the parameters as key/value pairs or a list of values. In addition to type checks, it also supports parameter defaults, optional parameters, and extra "slurpy" parameters.

This Perl module provides a central location for modules to report monitoring metrics, such as counters of the number of times interesting events have happened, and programs to collect up and send those metrics to monitoring services.

This package consists of a Perl module for date calculations based on the Gregorian calendar, thereby complying with all relevant norms and standards: ISO/R 2015-1971, DIN 1355 and, to some extent, ISO 8601 (where applicable).

The Digest::HMAC module follows the common Digest:: interface for the RFC 2104 HMAC mechanism.

This package allows you to define different interpreters for different test scripts with Test::Run.

This module fills a gap in Moose by adding method parameter validation to Moose.

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".

This package contains SGMLS.pm, a perl5 class library for parsing the output from an SGML parser such as OpenSP. It also includes the sgmlspl command, an Perl script showcasing how the library can be used.

The inc::latest module helps bootstrap configure-time dependencies for CPAN distributions. These dependencies get bundled into the inc directory within a distribution and are used by Makefile.PL or Build.PL.

The Digest::JHash module allows you to use the fast JHash hashing algorithm developed by Bob Jenkins from within Perl programs. The algorithm takes as input a message of arbitrary length and produces as output a 32-bit "message digest" of the input in the form of an unsigned long integer.