为什么Composer下载了Zend Framework 2，即使它已经下载了？

Question

First of all, I had already installed and configured zend framework 2 in include_path of php.ini. But when I was installed zend framework skeleton application using composer install then it do some process and then again download whole zend framework 2 in to 'vendor' directory (which is automatically created in my application directory). Please help me that why composer again download and install whole framework and why it do not use already installed copy?

Answer 1

The short answer is that composer is designed to install dependencies on a per application level rather than globally. So all dependencies specified in the composer.json file will be pulled in to your project's vendor folder. This will happen even if you happen to have a certain dependency installed globally on your system.