=head1 NAME

C<Devel::MAT::Tool> - extend the ability of C<Devel::MAT>

=head1 DESCRIPTION

The C<Devel::MAT::Tool::> namespace provides a place to store plugins that
extend the abilities of L<Devel::MAT>. Such tools can be used to provide extra
analysis or display capabilities on the UI. It can interact with the UI by
calling methods in the L<Devel::MAT::UI> package.

A tool should be placed in the namespace and provide an object class. It does
not need to inherit from anything specific. Tools will be constructed lazily
by the UI as requested by the user.

=head1 METHODS

The following methods should provided on a tool class.

=head2 $display = CLASS->FOR_UI

If the tool should be displayed on the UI's C<Tools> menu, this constant
method should be provided to return a true value.

=head2 $tool = CLASS->new( $pmat, %args )

Constructs the instance of the tool. If the tool does not need to store any
instance data, this may instead simply return the class name.

This will be passed the L<Devel::MAT> object itself, and additional arguments
as named parameters.

=over 4

=item progress => CODE

If provided, the tool should call this function occasionally if it has to
perform a long-running task, such as a calculation across the entire heap,
that may take some time. The function should be passed a status string to
indicate progress on the UI; the UI will display it and flush pending input
events to ensure the interface remains moderately responsive to user input.

=back

=head2 $tool->init_ui( $ui )

Asks the tool to initialise any UI elements it may require, by calling methods
on the given C<$ui>. This may be an object, or the package name
C<Devel::MAT::UI> directly.

=cut

=head1 SVs

Tools may, and are encouraged to where appropriate, add methods to the
C<Devel::MAT::SV> package to access results of analysis or perform other
related activities. All SVs are implemented as blessed HASH references, and
tools may use keys beginning C<tool_...> in it. Key and method names should be
namespaced appropriately according to the tool name, to avoid collisions.

=cut

=head1 AUTHOR

Paul Evans <leonerd@leonerd.org.uk>

=cut
