Message:

I am totally new to Symfony. After I installed Symfony on my local ddev machine, I get this error

Fatal error: Composer detected issues in your platform: Your Composer dependencies require a PHP version ">= 8.1.0". You are running 7.4.29. in /var/www/html/symfony/vendor/composer/platform_check.php on line 24

I tried to composer install --ignore-platform-reqs as well, and soon as I run it, I get this error message

Parse error: syntax error, unexpected '|', expecting variable (T_VARIABLE) in /var/www/html/symfony/vendor/psr/log/src/LoggerInterface.php on line 30

My php version is

❯ php -v

PHP 8.1.6 (cli) (built: May 12 2022 23:44:22) (NTS)

Copyright (c) The PHP Group

Zend Engine v4.1.6, Copyright (c) Zend Technologies

    with Zend OPcache v8.1.6, Copyright (c), by Zend Technologies

Compose.json

    "type": "project",

    "license": "proprietary",

    "minimum-stability": "stable",

    "prefer-stable": true,

    "require": {

        "php": ">=7.2.5",

        "ext-ctype": "*",

        "ext-iconv": "*",

        "symfony/console": "*",

        "symfony/dotenv": "*",

        "symfony/flex": "^1.17|^2",

        "symfony/framework-bundle": "*",

        "symfony/runtime": "*",

        "symfony/yaml": "*"

    },

    "require-dev": {

    },

    "config": {

Thanks for help

Update

If you are using docker/ddev, make sure to set the php version inside `config.yml`

Make sure to php version matches the symfony requirements

name: ddev-gitpod

type: drupal9

docroot: web

php_version: "8.1"

webserver_type: nginx-fpm

router_http_port: "80"

router_https_port: "443"

xdebug_enabled: false

additional_hostnames: []

additional_fqdns: []

database:

  type: mariadb

  version: "10.3"

nfs_mount_enabled: false

mutagen_enabled: false

use_dns_when_possible: true

composer_version: ""

web_environment: []

nodejs_version: "16"

---

My Answer:
that is not compatible with your current PHP version. Please make sure you are using a PHP version that meets the requirements of your Composer dependencies. You can check the PHP version required by your dependencies in the composer.json file or by running the command `composer show -i`.