NAME

Data::Validate::Type - Public interface encapsulating Params::Util to offer data type validation functions that pass PerlCritic.

VERSION

Version 1.2.0

SYNOPSIS

        # Call with explicit package name.
        use Data::Validate::Type;
        if ( Data::Validate::Type::is_string( 'test' ) )
        {
                # ...
        }

        # Import specific functions.
        use Data::Validate::Type qw( is_string );
        if ( is_string( 'test' ) )
        {
                # ...
        }

        # Import functions for a given paradigm.
        use Data::Validate::Type qw( :boolean_tests );
        if ( is_string( 'test' ) )
        {
                # ...
        }

DESCRIPTION

Params::Util is a wonderful module, but suffers from a few drawbacks:

• Function names start with an underscore, which is usually used to indicate private functions.

• Function names are uppercase, which is usually used to indicate file handles or constants.

• Function names don't pass PerlCritic's validation, making them problematic to import.

• Functions use by default the convention that collection that collections need to not be empty to be valid (see _ARRAY0/_ARRAY for example), which is counter-intuitive.

Those drawbacks are purely cosmetic and don't affect the usefulness of the functions, so this module encapsulates the functions to offer an API that fixes these problems.

Please note that I prefer long function names that are descriptive, to arcane short ones. This increases readability, and the bulk of the typing can be spared with the use of a good IDE like Padre.

Also, this is work in progress - I haven't encapsulated all the functions from Params::Util yet, and if you need one in particular feel free to contact me.

BOOLEAN TEST FUNCTIONS

Functions in this group return a boolean to indicate whether the parameters passed match the test(s) specified by the functions or not.

All the boolean functions can be imported at once in your namespace with the following line:

        use Data::Validate::Type qw( :boolean_tests );

is_string()

Return a boolean indicating if the variable passed is a string.

        my $is_string = Data::Validate::Type::is_string( $variable );

Note: 0 and '' (empty string) are valid strings.

Parameters:

• allow_empty

  Boolean, default 1. Allow the string to be empty or not.

is_arrayref()

Return a boolean indicating if the variable passed is an arrayref that can be dereferenced into an array.

        my $is_arrayref = Data::Validate::Type::is_arrayref( $variable );
        
        my $is_arrayref = Data::Validate::Type::is_arrayref(
                $variable,
                allow_empty => 1,
                no_blessing => 0,
        );
        
        # Check if the variable is an arrayref of hashrefs.
        my $is_arrayref = Data::Validate::Type::is_arrayref(
                $variable,
                allow_empty           => 1,
                no_blessing           => 0,
                element_validate_type =>
                        sub
                        {
                                return Data::Validate::Type::is_hashref( $_[0] );
                        },
        );

Parameters:

• allow_empty

  Boolean, default 1. Allow the array to be empty or not.

• no_blessing

  Boolean, default 0. Require that the variable is not blessed.

• element_validate_type

  None by default. Set it to a coderef to validate the elements in the array. The coderef will be passed the element to validate as first parameter, and it must return a boolean indicating whether the element was valid or not.

is_hashref()

Return a boolean indicating if the variable passed is a hashref that can be dereferenced into a hash.

        my $is_hashref = Data::Validate::Type::is_hashref( $variable );
        
        my $is_hashref = Data::Validate::Type::is_hashref(
                $variable,
                allow_empty => 1,
                no_blessing => 0,
        );

Parameters:

• allow_empty

  Boolean, default 1. Allow the array to be empty or not.

• no_blessing

  Boolean, default 0. Require that the variable is not blessed.

is_coderef()

Return a boolean indicating if the variable passed is an coderef that can be dereferenced into a block of code.

        my $is_coderef = Data::Validate::Type::is_coderef( $variable );

is_number()

Return a boolean indicating if the variable passed is a number.

        my $is_number = Data::Validate::Type::is_number( $variable );
        my $is_number = Data::Validate::Type::is_number(
                $variable,
                positive => 1,
        );
        my $is_number = Data::Validate::Type::is_number(
                $variable,
                strictly_positive => 1,
        );

Parameters:

• strictly_positive

  Boolean, default 0. Set to 1 to check for a strictly positive number.

• positive

  Boolean, default 0. Set to 1 to check for a positive number.

is_instance()

Return a boolean indicating if the variable is an instance of the given class.

Note that this handles inheritance properly, so it will return true if the variable is an instance of a subclass of the class given.

        my $is_instance = Data::Validate::Type::is_instance(
                $variable,
                class => $class,
        );

Parameters:

• class

  Required, the name of the class to check the variable against.

ASSERTION-BASED FUNCTIONS

Functions in this group do not return anything, but will die when the parameters passed don't match the test(s) specified by the functions.

All the assertion test functions can be imported at once in your namespace with the following line:

        use Data::Validate::Type qw( :assertions );

assert_string()

Die unless the variable passed is a string.

        Data::Validate::Type::assert_string( $variable );

Note: 0 and '' (empty string) are valid strings.

Parameters:

• allow_empty

  Boolean, default 1. Allow the string to be empty or not.

assert_arrayref()

Die unless the variable passed is an arrayref that can be dereferenced into an array.

        Data::Validate::Type::assert_arrayref( $variable );
        
        Data::Validate::Type::assert_arrayref(
                $variable,
                allow_empty => 1,
                no_blessing => 0,
        );
        
        # Require the variable to be an arrayref of hashrefs.
        Data::Validate::Type::assert_arrayref(
                $variable,
                allow_empty           => 1,
                no_blessing           => 0,
                element_validate_type =>
                        sub
                        {
                                return Data::Validate::Type::is_hashref( $_[0] );
                        },
        );

Parameters:

• allow_empty

  Boolean, default 1. Allow the array to be empty or not.

• no_blessing

  Boolean, default 0. Require that the variable is not blessed.

• element_validate_type

  None by default. Set it to a coderef to validate the elements in the array. The coderef will be passed the element to validate as first parameter, and it must return a boolean indicating whether the element was valid or not.

assert_hashref()

Die unless the variable passed is a hashref that can be dereferenced into a hash.

        Data::Validate::Type::assert_hashref( $variable );
        
        Data::Validate::Type::assert_hashref(
                $variable,
                allow_empty => 1,
                no_blessing => 0,
        );

Parameters:

• allow_empty

  Boolean, default 1. Allow the array to be empty or not.

• no_blessing

  Boolean, default 0. Require that the variable is not blessed.

assert_coderef()

Die unless the variable passed is an coderef that can be dereferenced into a block of code.

        Data::Validate::Type::assert_coderef( $variable );

assert_number()

Die unless the variable passed is a number.

        Data::Validate::Type::assert_number( $variable );
        Data::Validate::Type::assert_number(
                $variable,
                positive => 1,
        );
        Data::Validate::Type::assert_number(
                $variable,
                strictly_positive => 1,
        );

Parameters:

• strictly_positive

  Boolean, default 0. Set to 1 to check for a strictly positive number.

• positive

  Boolean, default 0. Set to 1 to check for a positive number.

assert_instance()

Die unless the variable is an instance of the given class.

Note that this handles inheritance properly, so it will not die if the variable is an instance of a subclass of the class given.

        Data::Validate::Type::assert_instance(
                $variable,
                class => $class,
        );

Parameters:

• class

  Required, the name of the class to check the variable against.

FILTERING FUNCTIONS

Functions in this group return the variable tested against when it matches the test(s) specified by the functions.

All the filtering functions can be imported at once in your namespace with the following line:

        use Data::Validate::Type qw( :filters );

filter_string()

Return the variable passed if it is a string, otherwise return undef.

        Data::Validate::Type::filter_string( $variable );

Note: 0 and '' (empty string) are valid strings.

Parameters:

• allow_empty

  Boolean, default 1. Allow the string to be empty or not.

filter_arrayref()

Return the variable passed if it is an arrayref that can be dereferenced into an array, otherwise undef.

        Data::Validate::Type::filter_arrayref( $variable );
        
        Data::Validate::Type::filter_arrayref(
                $variable,
                allow_empty => 1,
                no_blessing => 0,
        );
        
        # Only return the variable if it is an arrayref of hashrefs.
        Data::Validate::Type::filter_arrayref(
                $variable,
                allow_empty           => 1,
                no_blessing           => 0,
                element_validate_type =>
                        sub
                        {
                                return Data::Validate::Type::is_hashref( $_[0] );
                        },
        );

Parameters:

• allow_empty

  Boolean, default 1. Allow the array to be empty or not.

• no_blessing

  Boolean, default 0. Require that the variable is not blessed.

• element_validate_type

  None by default. Set it to a coderef to validate the elements in the array. The coderef will be passed the element to validate as first parameter, and it must return a boolean indicating whether the element was valid or not.

filter_hashref()

Return the variable passed if it is a hashref that can be dereferenced into a hash, otherwise return undef.

        Data::Validate::Type::filter_hashref( $variable );
        
        Data::Validate::Type::filter_hashref(
                $variable,
                allow_empty => 1,
                no_blessing => 0,
        );

Parameters:

• allow_empty

  Boolean, default 1. Allow the array to be empty or not.

• no_blessing

  Boolean, default 0. Require that the variable is not blessed.

filter_coderef()

REturn the variable passed if it is a coderef that can be dereferenced into a block of code, otherwise return undef.

        Data::Validate::Type::filter_coderef( $variable );

filter_number()

Return the variable passed if it is a number, otherwise return undef.

        Data::Validate::Type::filter_number( $variable );
        Data::Validate::Type::filter_number(
                $variable,
                positive => 1,
        );
        Data::Validate::Type::filter_number(
                $variable,
                strictly_positive => 1,
        );

Parameters:

• strictly_positive

  Boolean, default 0. Set to 1 to check for a strictly positive number.

• positive

  Boolean, default 0. Set to 1 to check for a positive number.

filter_instance()

Return the variable passed if it is an instance of the given class.

Note that this handles inheritance properly, so it will return the variable if it is an instance of a subclass of the class given.

        Data::Validate::Type::filter_instance(
                $variable,
                class => $class,
        );

Parameters:

• class

  Required, the name of the class to check the variable against.

AUTHOR

Guillaume Aubert, <aubertg at cpan.org>.

BUGS

Please report any bugs or feature requests to bug-data-validate-type at rt.cpan.org, or through the web interface at http://rt.cpan.org/NoAuth/ReportBug.html?Queue=Data-Validate-Type. I will be notified, and then you'll automatically be notified of progress on your bug as I make changes.

SUPPORT

You can find documentation for this module with the perldoc command.

        perldoc Data::Validate::Type

You can also look for information at:

• RT: CPAN's request tracker

  http://rt.cpan.org/NoAuth/Bugs.html?Dist=Data-Validate-Type

• AnnoCPAN: Annotated CPAN documentation

  http://annocpan.org/dist/Data-Validate-Type

• CPAN Ratings

  http://cpanratings.perl.org/d/Data-Validate-Type

• Search CPAN

  http://search.cpan.org/dist/Data-Validate-Type/

COPYRIGHT & LICENSE

Copyright 2012 Guillaume Aubert.

This program is free software; you can redistribute it and/or modify it under the terms of the Artistic License.

See http://dev.perl.org/licenses/ for more information.

cpanm Data::Validate::Type

perl -MCPAN -e shell
install Data::Validate::Type