Getting Started

Now that you’ve learned the concepts, let’s put them into practice.

Requirements

• PHP 8.4+
• Composer

Installation

composer create-project be-framework/skeleton my-project --stability dev
cd my-project

Run the Example

composer dev

Output:

Hello World

That’s it! Let’s look at the code.

Project Structure

bin/
└── be.php                  # CLI entrypoint
src/
├── Input/
│   └── HelloInput.php      # Starting point
├── Final/
│   └── Hello.php           # Destination
├── Reason/
│   └── Greeting.php        # Transcendent capability
├── Semantic/
│   └── Name.php            # Semantic variables
├── Exception/
│   └── EmptyNameException.php
└── Module/
    └── AppModule.php       # DI configuration

The Code

Input Class

#[Be([Hello::class])]
final readonly class HelloInput
{
    public function __construct(
        public string $name
    ) {}
}

The #[Be] attribute declares the destiny—what this input will become. It accepts a single class or an array of candidates; the array form is used here so that adding a second destiny later is a one-line change.

Final Class

final readonly class Hello
{
    public string $greeting;

    public function __construct(
        #[Input] string $name,
        #[Inject] Greeting $greeting,
    ) {
        $this->greeting = "{$greeting->greeting} {$name}";
    }
}

• #[Input] receives data from the previous stage (HelloInput)
• #[Inject] receives Transcendence (capability from outside)

Reason Class

final class Greeting
{
    public string $greeting = 'Hello';
}

The Greeting provides the transcendent capability—the power to greet.

Executing Metamorphosis

$injector = new Injector(new AppModule());
$becoming = $injector->getInstance(BecomingInterface::class);

$input = new HelloInput('World');
$hello = $becoming($input);

echo $hello->greeting;  // "Hello World"

What Just Happened?

HelloInput('World')
    ↓ Becoming executes
Hello (with Greeting injected)
    → "Hello World"

The input didn’t “do” anything—it became Hello through metamorphosis.

Try Semantic Validation

composer dev runs php bin/be.php 'hello?name=World'. Pass an empty name this time:

php bin/be.php 'hello?name='

Output:

名前は空にできません。

Semantic/Name.php declares that a $name cannot be empty, so HelloInput('') never comes into existence. The message comes from the #[Message] attribute on EmptyNameException; bin/be.php prints its Japanese version.

Key Concepts Demonstrated

Next Steps

Ready for a more complete example with Being classes and branching? Continue to Tutorial →

Or revisit the concepts:

• Input Classes - Starting points
• Final Objects - Destinations
• Semantic Variables - Domain ontology