php-8-3

name	php-8.3
description	ACTIVATE when writing PHP class constants in a PHP 8.3+ project. Covers: mandatory typed class constants and default visibility. DO NOT use for: general PHP syntax, PHP 8.2 features (see php-8.2).
version	1.2

PHP 8.3 Conventions

Two project conventions for class constants: type them, and keep them private by default.

Typed Constants

// AVOID
private const TRANSLATION_DOMAIN = 'messages';
private const MAX_ITEMS = 100;

// CORRECT
private const string TRANSLATION_DOMAIN = 'messages';
private const int MAX_ITEMS = 100;

Supported types: string, int, float, bool, array, class/interface names, mixed.

Visibility defaults

Default to private for class constants. Promote to public only when an external consumer (template, sibling class, public API) actually reads it. Don't mirror the visibility of a neighbor constant without checking — the principle of least visibility wins over consistency.

// AVOID — public by default, no external consumer
final class CheckoutController
{
    public const string ROUTE_NAME = 'checkout_index';
    public const string CART_COOKIE_NAME = 'cart_token';
    // ...
}

// CORRECT — private until proven otherwise
final class CheckoutController
{
    private const string ROUTE_NAME = 'checkout_index';
    private const string CART_COOKIE_NAME = 'cart_token';
    // ...
}

// CORRECT — public is justified, the constant is actually read elsewhere
final class OrderConfirmationController
{
    // Read by templates/order/index.html.twig via path('order_confirmation', ...)
    // and by CheckoutController to redirect after a successful checkout.
    public const string ROUTE_NAME = 'order_confirmation';
}

Decision heuristic before writing public const: grep for usages outside the declaring class. No hit → private. Hit → public and add a brief comment naming the consumer (helps future cleanup when the consumer disappears).