What does Request $ request mean by writing this Request?

PublicfunctionUser (Request $ request) {} public function User (Request $ request ){}

Reply content:

Public function User (Request $ request ){}

Http://php.net/manual/zh/language.oop5.typehinting.php

PHP 5 can use type constraints.
Function parameters can be specified as objects (specify the class name in the function prototype), interfaces, arrays (from PHP 5.1) or callable (from PHP 5.4 ).

Official example

/* ** Test function * The first parameter must be an object of the OtherClass */public function test (OtherClass $ otherclass) {echo $ otherclass-> var ;}

Request is a class, and $ request is an object generated by it! Of course, it can also be an interface or something!