Provided by: libbread-board-perl_0.32-2_all bug


       Bread::Board - A solderless way to wire up your application components


       version 0.32


         use Bread::Board;

         my $c = container 'MyApp' => as {

             service 'log_file_name' => "logfile.log";

             service 'logger' => (
                 class        => 'FileLogger',
                 lifecycle    => 'Singleton',
                 dependencies => [ 'log_file_name' ],

             container 'Database' => as {
                 service 'dsn'      => "dbi:SQLite:dbname=my-app.db";
                 service 'username' => "user234";
                 service 'password' => "****";

                 service 'dbh' => (
                     block => sub {
                         my $s = shift;
                         require DBI;
                         ) || die "Could not connect";
                     dependencies => [ 'dsn', 'username', 'password' ]

             service 'application' => (
                 class        => 'MyApplication',
                 dependencies => {
                     logger => 'logger',
                     dbh    => 'Database/dbh',


         no Bread::Board; # removes keywords

         # get an instance of MyApplication
         # from the container
         my $app = $c->resolve( service => 'application' );

         # now user your MyApplication
         # as you normally would ...


       Bread::Board is an inversion of control framework with a focus on dependency injection and
       lifecycle management. It's goal is to help you write more decoupled objects and components
       by removing the need for you to manually wire those objects/components together.

       Want to know more? See the Bread::Board::Manual.

         |          A B C D E   F G H I J          |
         | o o |  1 o-o-o-o-o v o-o-o-o-o 1  | o o |
         | o o |  2 o-o-o-o-o   o-o-o-o-o 2  | o o |
         | o o |  3 o-o-o-o-o   o-o-o-o-o 3  | o o |
         | o o |  4 o-o-o-o-o   o-o-o-o-o 4  | o o |
         | o o |  5 o-o-o-o-o   o-o-o-o-o 5  | o o |
         |     |  6 o-o-o-o-o   o-o-o-o-o 6  |     |
         | o o |  7 o-o-o-o-o   o-o-o-o-o 7  | o o |
         | o o |  8 o-o-o-o-o   o-o-o-o-o 8  | o o |
         | o o |  9 o-o-o-o-o   o-o-o-o-o 9  | o o |
         | o o | 10 o-o-o-o-o   o-o-o-o-o 10 | o o |
         | o o | 11 o-o-o-o-o   o-o-o-o-o 11 | o o |
         |     | 12 o-o-o-o-o   o-o-o-o-o 12 |     |
         | o o | 13 o-o-o-o-o   o-o-o-o-o 13 | o o |
         | o o | 14 o-o-o-o-o   o-o-o-o-o 14 | o o |
         | o o | 15 o-o-o-o-o   o-o-o-o-o 15 | o o |
         | o o | 16 o-o-o-o-o   o-o-o-o-o 16 | o o |
         | o o | 17 o-o-o-o-o   o-o-o-o-o 17 | o o |
         |     | 18 o-o-o-o-o   o-o-o-o-o 18 |     |
         | o o | 19 o-o-o-o-o   o-o-o-o-o 19 | o o |
         | o o | 20 o-o-o-o-o   o-o-o-o-o 20 | o o |
         | o o | 21 o-o-o-o-o   o-o-o-o-o 21 | o o |
         | o o | 22 o-o-o-o-o   o-o-o-o-o 22 | o o |
         | o o | 22 o-o-o-o-o   o-o-o-o-o 22 | o o |
         |     | 23 o-o-o-o-o   o-o-o-o-o 23 |     |
         | o o | 24 o-o-o-o-o   o-o-o-o-o 24 | o o |
         | o o | 25 o-o-o-o-o   o-o-o-o-o 25 | o o |
         | o o | 26 o-o-o-o-o   o-o-o-o-o 26 | o o |
         | o o | 27 o-o-o-o-o   o-o-o-o-o 27 | o o |
         | o o | 28 o-o-o-o-o ^ o-o-o-o-o 28 | o o |

       Loading this package will automatically load the rest of the packages needed by your
       Bread::Board configuration.


       The functions of this package provide syntactic sugar to help you build your Bread::Board
       configuration. You can build such a configuration by constructing the objects manually
       instead, but your code may be more difficult to understand.

       container ($name, &body)
           This function constructs and returns an instance of Bread::Board::Container.  The
           (optional) &body block may be used to add services or sub-containers within the newly
           constructed container. Usually, the block is not passed directly, but passed using the
           "as" function.

           For example,

             container 'MyWebApp' => as {
                 service my_dispatcher => (
                     class => 'MyWebApp::Dispatcher',

           If $name starts with '+', and the container is being declared inside another
           container, then this declaration will instead extend an existing container with the
           name $name (without the '+').

       container ($container_instance, &body)
           In many cases, subclassing Bread::Board::Container is the easiest route to getting
           access to this framework. You can do this and still get all the benefits of the
           syntactic sugar for configuring that class by passing an instance of your container
           subclass to "container".

           You could, for example, configure your container inside the "BUILD" method of your

             package MyWebApp;
             use Moose;

             extends 'Bread::Board::Container';

             sub BUILD {
                 my $self = shift;

                 container $self => as {
                     service dbh => ( ... );

       container ($name, [ @parameters ], &body)
           A third way of using the "container" function is to build a parameterized container.
           These are useful as a way of providing a placeholder for parts of the configuration
           that may be provided later. You may not use an instance object in place of the $name
           in this case.

           For more detail on how you might use parameterized containers, see "Parameterized
           Containers" in Bread::Board::Manual::Concepts::Advanced.

       as (&body)
           This is just a replacement for the "sub" keyword that is easier to read when defining

       service ($name, $literal | %service_description)
           Within the "as" blocks for your containers, you may construct services using the
           "service" function. This can construct several different kinds of services based upon
           how it is called.

           To build a literal service (a Bread::Board::Literal object), just specify a scalar
           value or reference you want to use as the literal value:

             # In case you need to adjust the gravitational constant of the Universe
             service gravitational_constant => 6.673E-11;

           To build a service using one of the injection services, just fill in all the details
           required to use that sort of injection:

             service search_service => (
                 class => 'MyApp::Search',
                 block => sub {
                     my $s = shift;
                     MyApp::Search->new($s->param('url'), $s->param('type'));
                 dependencies => {
                     url => 'search_url',
                 parameters => {
                     type => { isa => 'Str', default => 'text' },

           The type of injection performed depends on the parameters used. You may use the
           "service_class" parameter to pick a specific injector class. For instance, this is
           useful if you need to use Bread::Board::SetterInjection or have defined a custom
           injection service.  If you specify a "block", block injection will be performed using
           Bread::Board::BlockInjection. If neither of these is present, constructor injection
           will be used with Bread::Board::ConstructorInjection (and you must provide the "class"

           The "dependencies" parameter takes a hashref of dependency names mapped to
           Bread::Board::Dependency objects, but there are several coercions and sugar functions
           available to make specifying dependencies as easy as possible. The simplest case is
           when the names of the services you're depending on are the same as the names that the
           service you're defining will be accessing them with.  In this case, you can just
           specify an arrayref of service names:

             service foo => (
                 dependencies => [ 'bar', 'baz' ],
                 # ...

           If you need to use a different name, you can specify the dependencies as a hashref

             service foo => (
                 dependencies => {
                     dbh => 'foo_dbh',
                 # ...

           You can also specify parameters when depending on a parameterized service:

             service foo => (
                 dependencies => [
                     { bar => { bar_param => 1 } },
                 # ...

           Finally, services themselves can also be specified as dependencies, in which case they
           will just be resolved directly:

             service foo => (
                 dependencies => {
                     dsn => Bread::Board::Literal->new(
                         name  => 'dsn',
                         value => 'dbi:mysql:mydb',
                 # ...

           As a special case, an arrayref of dependencies will be interpreted as a service which
           returns an arrayref containing the resolved values of those dependencies:

             service foo => (
                 dependencies => {
                     # items will resolve to [ $bar_service->get, $baz_service->get ]
                     items => [
                         Bread::Board::Literal->new(name => 'baz', value => 'BAZ'),
                 # ...

           If the $name starts with a '+', the service definition will instead extend an existing
           service with the given $name (without the '+'). This works similarly to the "has
           '+foo'" syntax in Moose. It is most useful when defining a container class where the
           container is built up in "BUILD" methods, as each class in the inheritance hierarchy
           can modify services defined in superclasses. The "dependencies" and "parameters"
           options will be merged with the existing values, rather than overridden. Note that
           literal services can't be extended, because there's nothing to extend. You can still
           override them entirely by declaring the service name without a leading '+'.

       depends_on ($service_path)
           The "depends_on" function creates a Bread::Board::Dependency object for the named
           $service_path and returns it.

       wire_names (@service_names)
           This function is just a shortcut for passing a hash reference of dependencies into the
           service. It is not typically needed, since Bread::Board can usually understand what
           you mean - these declarations are all equivalent:

             service foo => (
                 class => 'Pity::TheFoo',
                 dependencies => {
                     foo => depends_on('foo'),
                     bar => depends_on('bar'),
                     baz => depends_on('baz'),

             service foo => (
                 class => 'Pity::TheFoo',
                 dependencies => wire_names(qw( foo bar baz )),

             service foo => (
                 class => 'Pity::TheFoo',
                 dependencies => {
                     foo => 'foo',
                     bar => 'bar',
                     baz => 'baz',

             service foo => (
                 class => 'Pity::TheFoo',
                 dependencies => [ qw(foo bar baz ) ],

       typemap ($type, $service | $service_path)
           This creates a type mapping for the named type. Typically, it is paired with the
           "infer" call like so:

             typemap 'MyApp::Model::UserAccount' => infer;

           For more details on what type mapping is and how it works, see

       infer (?%hints)
           This is used with "typemap" to help create the typemap inference. It can be used with
           no arguments to do everything automatically. However, in some cases, you may want to
           pass a service instance as the argument or a hash of service arguments to change how
           the type map works. For example, if your type needs to be constructed using a setter
           injection, you can use an inference similar to this:

             typemap 'MyApp::Model::UserPassword' => infer(
                 service_class => 'Bread::Board::SetterInjection',

           For more details on what type mapping is and how it works, see

       include ($file)
           This is a shortcut for loading a Bread::Board configuration from another file.

             include "";

           The above is pretty much identical to running:

             do "";

           However, you might find it more readable to use "include".

       alias ($service_name, $service_path, %service_description)
           This helper allows for the creation of service aliases, which allows you to define a
           service in one place and then reuse that service with a different name somewhere else.
           This is sort of like a symbolic link for services. Aliases will be resolved
           recursively, so an alias can alias an alias.

           For example,

             service file_logger => (
                 class => 'MyApp::Logger::File',

             alias my_logger => 'file_logger';


       These are not exported, but might be helpful to you.

       set_root_container ($container)
           You may use this to set a top-level root container for all container definitions.

           For example,

             my $app = container MyApp => as { ... };


             my $config = container Config => as { ... };

           Here the $config container would be created as a sub-container of $app.


       Thanks to Daisuke Maki for his contributions and for really pushing the development of
       this module along.

       Chuck "sprongie" Adams, for testing/using early (pre-release) versions of this module, and
       some good suggestions for naming it.

       Matt "mst" Trout, for finally coming up with the best name for this module.


       Bread::Board is the right tool for this job
       <> Thomas
       Klausner showing a use-case for Bread::Board.


           This provides more powerful syntax for writing Bread::Board container classes.

       IOC Bread::Board is basically my re-write of IOC.



       All complex software has bugs lurking in it, and this module is no exception. If you find
       a bug please either email me, or add the bug to Github Issues.


       Stevan Little <>


       This software is copyright (c) 2014 by Infinity Interactive.

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