NAME
    Crypt::XkcdPassword - see http://xkcd.com/936/

SYNOPSIS
     use 5.010;
     use Crypt::XkcdPassword;
 
     say Crypt::XkcdPassword->make_password;

DESCRIPTION
    Yet another password generator module inspired by <http://xkcd.com/936/>.

  Constructor
    *   `new(%attr)`

        Creates a new generator. A single generator can be used to generate as
        many passwords as you like.

  Attributes
    This is a Moo-based class.

    *   `words`

        A string which will be appended to `Crypt::XkcdPassword::Words::` to
        form a class name which will be used as a source for words. The
        default is "EN", which means the class used as a source for words is
        `Crypt::XkcdPassword::Words::EN`.

        `Crypt::XkcdPassword::Words::EN` is a list of 10,000 common English
        words.

        `Crypt::XkcdPassword::Words::EN::Roget` is a list of about 8500 words.
        The words are less questionable, but as there are fewer of them, pass
        phrases will be chosen from a smaller pool, thus slightly more
        guessable.

        Also supplied is "IT", a list of 20,000 common Italian words.

    *   `rng`

        A coderef for generating a random number. The coderef is called and
        passed a single numeric argument. The coderef is expected to generate
        a random, positive integer, smaller than the argument. The default is:

         sub { int(rand($_[0])) }

        Perl's default random number generator is often though insufficient
        for practical cryptography, so you may wish to use another random
        number generator.

  Methods
    *   `make_password($size, $filter)`

        Returns the password as a string.

        $size is the length of the password in words. It defaults to 4. For
        the English dictionary that provides over 47 bits of entropy; for the
        Italian dictionary (which has twice as many words), about 56 bits of
        entropy.

        $filter is a test against which each word is checked. It can be a sub
        returning true if the word is OK, or a regular expression matching OK
        words. Words which are not OK will be excluded from passwords. The
        default is to allow any words found in the provided dictionary.

        For reference, 47 bits of entropy is roughly equivalent to an eight
        digit random case-sensitive alphanumeric password (i.e. 62^8).

        This can be called as an object method, or (if you have no desire to
        change the defaults for the `rng` and `words` attributes) as a class
        method. That is, the first line of the example below is a shortcut for
        the second line:

         say Crypt::XkcdPassword->make_password($size);
         say Crypt::XkcdPassword->new->make_password($size);

        Note that the passphrases returned may not be ASCII-safe, and may
        sometimes be inappropriate for uttering in polite company. See
        Crypt::XkcdPassword::Examples for ways of using $filter to resolve
        this situation.

    *   `chars`

        No-op, provided for compatibility with Data::SimplePassword.

    *   `provider`

        No-op, provided for compatibility with Data::SimplePassword.

BUGS
    Please report any bugs to
    <http://rt.cpan.org/Dist/Display.html?Queue=Crypt-XkcdPassword>.

SEE ALSO
    Crypt::XkcdPassword::Examples - how to do stuff with this module.

    Data::SimplePassword - I borrowed this module's interface, so it should
    mostly be possible to s/Data::SimplePassword/Crypt::XkcdPassword/.

    Crypt::PW44 - similar to this one, but with a smaller list of words.

    <http://xkcd.com/936/>.

AUTHOR
    Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE
    This software is copyright (c) 2012, 2014 by Toby Inkster.

    This is free software; you can redistribute it and/or modify it under the
    same terms as the Perl 5 programming language system itself.

DISCLAIMER OF WARRANTIES
    THIS PACKAGE IS PROVIDED "AS IS" AND WITHOUT ANY EXPRESS OR IMPLIED
    WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
    MERCHANTIBILITY AND FITNESS FOR A PARTICULAR PURPOSE.

