Path::Iterator::Rule iterates over files and directories to identify ones matching a user-defined set of rules. The API is based heavily on File::Find::Rule, but with more explicit distinction between matching rules and options that influence how directories are searched. A Path::Iterator::Rule object is a collection of rules (match criteria) with methods to add additional criteria. Options that control directory traversal are given as arguments to the method that generates an iterator.

A summary of features for comparison to other file finding modules:

• provides many helper methods for specifying rules

• offers (lazy) iterator and flattened list interfaces

• custom rules implemented with callbacks

• breadth-first (default) or pre- or post-order depth-first searching

• follows symlinks (by default, but can be disabled)

• directories visited only once (no infinite loop; can be disabled)

• doesn't chdir during operation

• provides an API for extensions

As a convenience, the PIR module is an empty subclass of this one that is less arduous to type for one-liners.

The Specio distribution provides classes for representing type constraints and coercion, along with syntax sugar for declaring them. Note that this is not a proper type system for Perl. Nothing in this distribution will magically make the Perl interpreter start checking a value's type on assignment to a variable. In fact, there's no built-in way to apply a type to a variable at all. Instead, you can explicitly check a value against a type, and optionally coerce values to that type.

Number::Range is an object-oriented interface to test if a number exists in a given range, and to be able to manipulate the range.

Text::SimpleTable draws simple ASCII tables.

The Text::Balanced module can be used to extract delimited text sequences from strings.

This module allows you to call isa, can, does, and DOES safely on things that may not be objects.

This module brings the speed advantages of Set::IntSpan (written by Steven McDougall) to arrays. Uses include manipulating grades, routing tables, or any other situation where you have mutually exclusive ranges of integers that map to given values.

This module provides a syntax plugin that implements exception-handling semantics in a form familiar to users of other languages, being built on a block labeled with the try keyword, followed by at least one of a catch or finally block.

Number::Format is a library for formatting numbers. Functions are provided for converting numbers to strings in a variety of ways, and to convert strings that contain numbers back into numeric form. The output formats may include thousands separators - characters inserted between each group of three characters counting right to left from the decimal point. The characters used for the decimal point and the thousands separator come from the locale information or can be specified by the user.

Probe::Perl provides methods for obtaining information about the currently running perl interpreter. It originally began life as code in the Module::Build project, but has been externalized here for general use.

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.

Software distributions released to the CPAN include a META.json or, for older distributions, META.yml, which describes the distribution, its contents, and the requirements for building and installing the distribution. The data structure stored in the META.json file is described in CPAN::Meta::Spec. CPAN::Meta provides a simple class to represent this distribution metadata (or distmeta), along with some helpful methods for interrogating that data.

PPIx::Utilities is a collection of functions for dealing with PPI objects, many of which originated in Perl::Critic. They are organized into modules by the kind of PPI class they relate to, by replacing the "PPI" at the front of the module name with "PPIx::Utilities", e.g. functionality related to PPI::Nodes is in PPIx::Utilities::Node.

Throwable is a role for classes that are meant to be thrown as exceptions to standard program flow.

Text::Sprintf::Named provides a sprintf equivalent with named conversions. Named conversions are sprintf field specifiers (like %s or %4d) only they are associated with the key of an associative array of parameters. So for example %(name)s will emit the name parameter as a string, and %(num)4d will emit the num parameter as a variable with a width of 4.

This module provides a class to monitor a directory for changes made to any file.

Carp::Assert::More is a set of handy assertion functions for Perl.

Devel::LexAlias provides the ability to alias a lexical variable in a subroutines scope to one of your choosing.

This module is a helper for installing, reading and finding configuration file locations. File::ConfigDir is a module to help out when Perl modules (especially applications) need to read and store configuration files from more than one location.

This is a backend for Package::Stash, which provides the functionality in a way that's less buggy and much faster. It will be used by default if it's installed, and should be preferred in all environments with a compiler.

Multidimensional disables multidimensional array emulation.

This module provides a general-purpose clone function to make deep copies of Perl data structures. It calls itself recursively to copy nested hash, array, scalar and reference types, including tied variables and objects.

This module implements the Brew edit distance that is very close to the dynamic programming technique used for the Wagner-Fischer (and so for the Levenshtein) edit distance.

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