Polyfill Php70 Laravel Package

Getting Started

This package is a compatibility polyfill—automatically loaded via Composer’s autoloader when your project requires it. No manual setup is needed. It quietly backfills missing PHP 7.0 features (like int, float, bool, void scalar types; declare(strict_types=1) support in older HHVM; IntlTimeZone, Error/Exception hierarchy changes, etc.) under the hood. To confirm it's active: check composer.json for "symfony/polyfill-php70" in require or require-dev, or inspect vendor/symfony/polyfill-php70. If you’re targeting PHP < 7.0 and using 7.0+ features (e.g., type declarations), this package ensures your code runs reliably across environments—even though PHP < 7.0 won’t natively understand those types, the polyfill prevents fatal errors on runtime.

Implementation Patterns

• Transparent Backporting: Use PHP 7.0+ syntax (e.g., void return types, int/string scalar types) without conditional checks—the polyfill detects capability and applies fallback logic only where needed.
• Framework Dependency: Often pulled transitively via Symfony components (e.g., symfony/http-foundation, symfony/console) or modern Laravel apps—even if you don’t explicitly require it.
• Testing Environments: Safely run test suites across legacy PHP versions (e.g., PHP 5.6) by including this polyfill in CI—avoiding manual version_compare() guards in your code.
• Library Development: Include as a dev dependency to write modern PHP while supporting older runtimes via polyfills, without blooting runtime dependencies for users on PHP ≥ 7.0.

Gotchas and Tips

• No Runtime Type Enforcement: Scalar type declarations (int, string, etc.) are not enforced on PHP < 7.0—even with this polyfill. It only prevents crashes, not type coercion. Use declare(strict_types=1) alongside for type safety where supported.
• Silent Failures: If you rely on PHP 7.0+ exception hierarchy (e.g., catching Throwable), verify runtime behavior: older PHP versions without the polyfill may fail silently on unhandled errors.
• Deprecation Status: As of Symfony 6+, this polyfill is deprecated—consider migrating to symfony/polyfill meta-package or dropping support for PHP < 7.0 entirely. Check README.md or Symfony’s deprecation policy for alternatives.
• Conflict with Native Extensions: Avoid installing alongside HHVM—polyfills assume Zend Engine semantics and may misbehave.
• Debug Tip: Use composer why symfony/polyfill-php70 to trace why it’s included; use composer why-not to assess removal impact.