/php-language-modern

name: php-language-modern
description: Use when writing modern non-framework PHP 8.1-8.5 — property hooks, asymmetric visibility, pipe operator, attributes, enums, readonly. Do NOT use for style (php-standards) or Laravel.
versions:
  php: "8.5"
user-invocable: false
references: references/php-85-features.md, references/php-84-features.md, references/php-81-83-baseline.md, references/attributes-over-docblocks.md, references/templates/modern-class.md
related-skills: php-standards

<objective> Covers modern PHP language features from 8.1 through 8.5 outside any framework: backed enums with methods/interfaces, first-class callable syntax, readonly properties/classes, the #[\Override] attribute, property hooks (get/set), asymmetric visibility, lazy objects (newLazyGhost()), the pipe operator (8.5), the clone() function with $withProperties, and #[\NoDiscard].

Its focus is language features that LLMs frequently get wrong or write in a pre-8.0 style — most notably using docblock annotations (@Route, @ORM\Column) instead of native #[Attribute] syntax, which is the #1 mistake this skill exists to prevent.

Do NOT use this skill for coding style, PSR compliance, or autoloading — that is php-standards. Do NOT use it for Laravel-specific syntax conventions — that lives in the Laravel plugin. </objective>

Modern PHP Language (8.1 → 8.5)

Agent Workflow (MANDATORY)

Before writing PHP, use `TeamCreate` to spawn 3 agents:

1. **fuse-ai-pilot:explore-codebase** - Detect the project's minimum PHP version (`composer.json` `require.php`, CI matrix) 2. **fuse-ai-pilot:research-expert** - Verify a feature's version + syntax on php.net before using it 3. **mcp__context7__query-docs** - Cross-check idiomatic usage

After writing, run **fuse-ai-pilot:sniper** for validation.

---

Overview

| Feature | Since | Use it for | |---------|-------|------------| | **Enums (backed + methods/interfaces)** | 8.1 | Closed sets of values with behavior | | **First-class callable syntax** `f(...)` | 8.1 | Passing callables without strings | | **readonly properties / classes** | 8.1 / 8.2 | Immutable value objects / DTOs | | **`#[\Override]`** | 8.3 | Fail-fast on broken inheritance | | **Property hooks** `get`/`set` | 8.4 | Computed/validated properties, no getter/setter boilerplate | | **Asymmetric visibility** `public private(set)` | 8.4 (static: 8.5) | Public read, restricted write | | **Lazy objects** `newLazyGhost()` | 8.4 | Deferred initialization in DI containers | | **Pipe operator** `\|>` | 8.5 | Left-to-right data transformation chains | | **`clone()` function + `$withProperties`** | 8.5 | Immutable "with" updates, incl. readonly | | **`#[\NoDiscard]`** | 8.5 | Enforce return-value consumption |

---

Critical Rules

1. **Attributes, never docblock annotations** - Native `#[Attribute]` replaces `@annotation` docblocks for routing, ORM, DI, validation. This is the #1 LLM mistake — see [attributes-over-docblocks.md](references/attributes-over-docblocks.md). 2. **Check the target PHP version first** - Never emit 8.5 syntax on an 8.1 project. Read `composer.json` `require.php` before choosing a feature. 3. **Prefer enums over class constants** for closed value sets — they carry type safety and methods. 4. **Prefer `readonly` + property hooks over hand-written getters/setters** — less boilerplate, enforced immutability. 5. **`declare(strict_types=1);`** at the top of every file.

---

Architecture

src/
├── Enum/
│   └── Status.php          # backed enum + interface + methods
├── ValueObject/
│   └── Money.php           # readonly class, clone() with $withProperties
└── Model/
    └── User.php            # property hooks, asymmetric visibility

→ See [modern-class.md](references/templates/modern-class.md) for complete working code

---

Reference Guide

Concepts

| Topic | Reference | When to Consult | |-------|-----------|-----------------| | **PHP 8.5 features** | [php-85-features.md](references/php-85-features.md) | Pipe operator, `clone()`, `#[\NoDiscard]`, static aviz | | **PHP 8.4 features** | [php-84-features.md](references/php-84-features.md) | Property hooks, aviz, lazy objects, `#[\Deprecated]` | | **8.1–8.3 baseline** | [php-81-83-baseline.md](references/php-81-83-baseline.md) | Enums, readonly, fibers, `#[\Override]` | | **Attributes vs docblocks** | [attributes-over-docblocks.md](references/attributes-over-docblocks.md) | Any metadata: routing, ORM, DI, validation |

Templates

| Template | When to Use | |----------|-------------| | [modern-class.md](references/templates/modern-class.md) | Writing a new class the modern way |

---

Best Practices

DO

• Read `require.php` before picking a feature version
• Use enums with interfaces + methods for stateful value sets
• Use property hooks for validation/computation instead of magic `__get`
• Use the pipe operator to flatten nested calls (8.5+)

DON'T

• Write `@Route`/`@ORM\Column` docblock annotations — use attributes
• Emit 8.4/8.5 syntax without confirming the project supports it
• Hand-roll getters/setters when hooks or `readonly` fit
• Guess a feature's version — verify on php.net