add example about optional argument #39

	name: CI

	on:
	push:
	branches: ["main"]
	pull_request:
	branches: ["main"]

	permissions:
	contents: read

	jobs:
	tests:
	name: Build
	runs-on: ubuntu-latest
	strategy:
	matrix:
	php:
	- 8.2
	- 8.3

	steps:
	- name: Set up PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php }}
	ini-values: zend.assertions=1

	- name: Checkout code
	uses: actions/checkout@v3

	- name: Validate composer.json and composer.lock
	run: composer validate --strict

	- name: Cache Composer packages
	id: composer-cache
	uses: actions/cache@v3
	with:
	path: vendor
	key: ${{ runner.os }}-php-${{ hashFiles('**/composer.lock') }}
	restore-keys: \|
	${{ runner.os }}-php-

	- name: Install dependencies
	run: composer install --classmap-authoritative

	- name: Run tests
	run: vendor/bin/phpunit tests

	psalm:
	name: Static Analyzer
	runs-on: ubuntu-latest

	steps:
	- name: Checkout code
	uses: actions/checkout@v3

	- name: Set up PHP
	uses: shivammathur/setup-php@v2
	with:
	php-version: ${{ matrix.php }}

	- name: Download dependencies
	run: composer install --classmap-authoritative

	- name: Phpstan
	run: vendor/bin/phpstan analyze src --level=max

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