PHP Namespace directory structure - php

Question

It is my understanding that namespaces are declared as follows : vendor\module\classname.
And directory structure would be:
/Acme
/Module1
/src
/Module1
/Class.php
And a valid way to instantiate the class is : new Acme\Module1\Class();
Are my assumptions correct? If so, what's the benefit of using the src folder?

Answer 1

Convention usually.
If you're using composer and you want to autoload your classes, it looks like you're trying to do PSR-0 autoloading.
So if you have "Acme": "src/"
Then in the same directory as your composer.json file would be a src folder, and in the src folder would be a Acme folder. All files in that folder would be namespace Acme; and all files in subdirectories of that folder would be namespace Acme\Subdirectory;.
In the console you need to type composer dump-autoload every time you make changes to the autoloading part of your composer.json file. (or for classmap autoloading, every time you add new files to directories being autoloaded.) This causes the files generated by composer to be updated. (you can find these files in the vendor/composer directory).
So if there was a src/Acme/Subdirectory/ClassName.php with a class in it named ClassName then to instantiate that class you could type new \Acme\Subdirectory\ClassName();
edit: so if this is your composer.json file
{
"autoload": {
"psr-0": {
"Acme": "src/"
}
}
}
then your directory structure would be something like this
/ProjectRoot
composer.json
/src
/Acme
/Module1
Class.php
And you would create a new instance of your class by typing
new \Acme\Module1\Class();