A DI Container without auto wiring

container-example.raku

class Container {
    has %!bindings = ();

    method set(Str $abstract, Callable $factory) {
        if not %!bindings{$abstract}:exists {
            %!bindings{$abstract} = $factory;
        }
    }

    method get(Str $abstract) {
        if %!bindings{$abstract}:exists {
            return %!bindings{$abstract}(self);
        }
    }
}

my $container = Container.new;

class Logger {
    method log(Str $text) {
        say $text;
    }
}

class SessionStorage {
    has Logger $!logger;

    method new(Logger $logger) {
        self.bless(logger => $logger);
    }

    method create() {
        $!logger.log('Session Created');
    }
}

class User {
    has SessionStorage $.session;

    method new(SessionStorage $session!) {
        self.bless(session => $session);
    }

    method authenticate() {
        $!session.create();
    }
}

$container.set('Logger', -> Container $c { Logger.new });
$container.set('SessionStorage', -> Container $c { SessionStorage.new($c.get('Logger')) });
$container.set('User', -> Container $c { User.new($c.get('SessionStorage')) });

my $user = $container.get('User');
$user.authenticate();