NAME
    Scalar::Does - like ref() but useful

SYNOPSIS
      my $object = bless {}, 'Some::Class';
  
      does($object, 'Some::Class');   # true
      does($object, '%{}');           # true
      does($object, 'HASH');          # true
      does($object, 'ARRAY');         # false

DESCRIPTION
    It has long been noted that Perl would benefit from a "does()" built-in.
    A check that "ref($thing) eq 'ARRAY'" doesn't allow you to accept an
    object that uses overloading to provide an array-like interface.

  Functions
    "does($scalar, $role)"
        Checks if a scalar is capable of performing the given role. The
        following (case-sensitive) roles are predefined:

        *   SCALAR or ${}

            Checks if the scalar can be used as a scalar reference.

        *   ARRAY or @{}

            Checks if the scalar can be used as an array reference.

        *   HASH or %{}

            Checks if the scalar can be used as a hash reference.

        *   CODE or &{}

            Checks if the scalar can be used as a code reference.

        *   GLOB or *{}

            Checks if the scalar can be used as a glob reference.

        *   REF

            Checks if the scalar can be used as a ref reference (i.e. a
            reference to another reference).

        *   LVALUE

            Checks if the scalar is a reference to a special lvalue (e.g.
            the result of "substr" or "splice").

        *   IO or <>

            Uses IO::Detect to check if the scalar is a filehandle or
            file-handle-like object.

            (The "<>" check is slightly looser, allowing objects which
            overload "<>", though overloading "<>" well can be a little
            tricky.)

        *   VSTRING

            Checks if the scalar is a vstring reference.

        *   FORMAT

            Checks if the scalar is a format reference.

        *   Regexp or qr

            Checks if the scalar can be used as a quoted regular expression.

        *   bool

            Checks if the scalar can be used as a boolean. (It's pretty rare
            for this to not be true.)

        *   ""

            Checks if the scalar can be used as a string. (It's pretty rare
            for this to not be true.)

        *   0+

            Checks if the scalar can be used as a number. (It's pretty rare
            for this to not be true.)

        *   ~~

            Checks if the scalar can be used on the right hand side of a
            smart match.

        For roles not on the predefined list above, the following behaviour
        is followed:

        1. If the given scalar is blessed, then "$scalar->DOES($role)" is
        called, and if that returns true, then "does" returns true.
        2. If the given *role* is blessed, and provides a "check" method,
        then "does" delegates to that. This allows MooseX::Types types to be
        used as roles. (But not Moose's type constraint strings.)

    "overloads($scalar, $role)"
        A function "overloads" (which just checks overloading) is also
        available.

    "blessed($scalar)", "reftype($scalar)"
        For convenience, this module can also re-export these functions from
        Scalar::Util.

  Export
    By default, only "does" is exported. This module uses Sub::Exporter, so
    functions can be renamed:

      use Scalar::Does does => { -as => 'performs_role' };

    Scalar::Does also plays some tricks with namespace::clean to ensure that
    any functions it exports to your namespace are cleaned up when you're
    finished with them. This ensures that if you're writing object-oriented
    code "does" and "overloads" will not be left hanging around as methods
    of your classes. Moose::Object provides a "does" method, and you should
    be able to use Scalar::Does without interfering with that.

  Custom Role Checks
      use Scalar::Does
        custom => { -as => 'does_array', -role => 'ARRAY' },
        custom => { -as => 'does_hash',  -role => 'HASH'  };
  
      does_array($thing);
      does_hash($thing);

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

SEE ALSO
    Scalar::Util, Moose::Role, MooseX::Types.

    <http://perldoc.perl.org/5.10.0/perltodo.html#A-does()-built-in>.

AUTHOR
    Toby Inkster <tobyink@cpan.org>.

COPYRIGHT AND LICENCE
    This software is copyright (c) 2012 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.