Simplified PHP Packages

__package__.php

<?php // file in root library/package directory 

package MyVendor\MyLibrary {

  // declare() not need to look like a function it's always assign operation: key => value
  declare strict_types = 1, strict_operators = 1;

  use SomeVendor\AutoloaderLibrary:Psr4Autoloader; // class loaded from other package
  declare class_autoload = new Psr4Autoloader(__PACKAGE__, __DIR__ . '/src');

  declare function_autoload = static function (string $functionName): void {
    @require_once __DIR__ . '/src/functions.php';
  };

  // dependency expectations
  expect SomeVendor\AutoloaderLibrary;

  // export only public symbols
  export class Foo; // class loaded through autoload
  export class FooBar\Baz; // class loaded through autoload
  export const FOO_CONST; // const declared in package root namespace inlined above
  export function my_library_function; // function loaded through autoload and declared in "functions.php"

  // group export
  export {
    class Foo,
    class FooBar\{Baz, BazBaz},
    const FOO_CONST,
    function my_library_function,
  };
  
  namespace {
    const FOO_CONST = 1;
    function my_another_library_function(): void {}
  }
}

__package__.yaml

version: "8.0"
name: MyVendor\MyLibrary
autoload: 
  classes: !psr4 "src/"
  functions: &file !require "src/functions.php"
  constants: *file
declare:
  strict_types: 1
  strict_operators: 1

src_Foo.php

<?php

package MyVendor\MyLibrary; // triggers autoload of "MyVendor\MyLibrary" package and load "__package__.php" file

// namespace; not needed in root package namespace

class Foo {}

src_FooBar_Baz.php

<?php

package MyVendor\MyLibrary;

namespace FooBar;

class Baz {}

src_FooBar_BazBaz.php

<?php

package MyVendor\MyLibrary;

namespace FooBar;

class BazBaz {}