> On Jun 29, 2024, at 2:32 AM, Michael Morris <tendo...@gmail.com> wrote:
> 
> Not replying to anyone in particular and instead doing a mild reset taking 
> into account the discussion that has gone before. 
> 
> So, I want to import a package. I'll create an index.php file at the root of 
> my website and populate it with this.
> 
> <?php
> import "./src/mymodule";
> 
> Now I'll create that directory and run a command `php mod init` in that 
> directory. Stealing this from Go, it's fairly straightforward though.  Now if 
> we look in the directory we will see two files.
> 
> php.mod
> php.sum
> 
> The second file I'll not be touching on but exists to track checksums of 
> downloaded packages - Composer does the same with its composer-lock.json file 
> which in turn was inspired by node's package-lock.json.
> 
> The php.mod file stands in for composer.json, but it isn't a json file.  It 
> would start something like this:
> 
> namespace mymodule
> php 10.0
> registry packagist.org/packages <http://packagist.org/packages>
> 
> We start with three directives - the root namespace is presumed to be the 
> directory name. If that isn't true this is a text file, change it.  PHP min 
> version should be straightforward. Registry details where we are going to go 
> get code from.  Suppose we want to use our own registry but fallback to 
> packagist.  That would be this:
> 
> namespace mymodule
> php 10.0
> registry (
>   github.com/myaccount <http://github.com/myaccount>
>   packagist.org/packages <http://packagist.org/packages>
> )
>  
> Multiple registry entries will be checked for the code in order.  Handling 
> auth tokens for restricted registries is outside of scope at the moment.

That is very Go-like, as you stated. 

However, be aware that in a Go project repo you are likely to have only one 
`go.mod` — or multiple if you have numerous CLI apps being generated — whereas 
every directory with Go code is a package (which I think is equivalent to what 
you are calling "module."

So I think your use of them here is conflating the two concepts. One is a 
project-wide concept and the other is a "package" concept.

Maybe you would be better to adopt `module` to mean project and `package` to 
mean packaged code as Go has them?

From here on I will refer to directory rather than module or package to avoid 
confusion. By directory I will mean what Go calls a "package" and what I think 
your original proposal called a "module."

A big difference between Go and PHP is that Go have a compiler that compiles 
into an executable before it runs. That is clearly not compatible with PHP, and 
why I was proposing that each directory could have a pre-compiled `.php.module` 
that could be pre-compiled, or compiled on the fly at first import.

Also, it is problematic to have `php.mod` and `php.sum` because web servers 
would serve them if not carefully configured hence why I went with a leading 
dot, e.g. `.php.module`

> 
> So let's build the module. We'll make a file called hello.phm.  The reason 
> for phm and not php is so that web SAPIs will not try to parse this code.  
> Further they can be configured to not even allow direct https access to these 
> files at all.
> 
> import "twig/twig";
> use \Twig\Loader\ArrayLoader;
> use \Twig\Environment;
> 
> $loader = new ArrayLoader([
>   'index' => 'Hello {{ name }}'
> ]);
> 
> $twig = new Environment($loader);
> 
> export $twig;
> 
> As mentioned in previous discussions, modules have their own variable scope.  
> Back in our index we need to receive the variable
> 
> <?php
> import $twig from "./src/mymodule"
> 
> $twig->render('index', ['name' => 'World']);


Aside from being familiar per Javascript, what is the argument to requiring the 
import of specific symbols vs just a package import, e.g.:

<?php
import "./src/mymodule"

mymodule->twig->render('index', ['name' => 'World']);

To me is seems to just add to boilerplate required.  Note that having 
`mymodule` everywhere you reference `twig` makes code a lot more 
self-documenting, especially on line 999 of a PHP file. 🙂

> 
>  If we load index.php in the web browser we should see "Hello World".  If we 
> look back in the mymodules folder we'll see the php.mod file has been updated
> 
> namespace mymodule
> php 10.0
> registry packagist.org/packages <http://packagist.org/packages>
> 
> imports (
>   twig/twig v3.10.3
>   symfony/deprecation-contracts v2.5 //indirect
>   symfony/polyfill-mbstring v1.3 //indirect
>   symfony/polyfill-php80 v1.22 //indirect
> )

Having a `php.sum` file is interesting but again, it should start with a period 
if so.

That said, I wonder if incorporating versioning does not make the scope of 
modules too big to complete?

> Note the automatically entered comment that marks the imported dependencies 
> of twig. Meanwhile the php.sum file will also be updated with the checksums 
> of these packages.
> 
> So why this instead of composer?  Well, a native implementation should be 
> faster, but also it might be able to deal with php extensions.
> 
> import "@php_mysqli"

I would like this, but I think hosting vendors would block it since extensions 
can have C bugs and create vulnerabilities for servers.

I have long thought PHP should kick off a new type of extension using WASM, 
which can be sandboxed. 

But I digress.

> 
> The @ marks that the extension is either a .so or .dll library, as I'll 
> hazard a guess that the resolution mechanic will be radically different from 
> the php language modules themselves - if it is possible at all. If it can be 
> done it will make working with packages that require extensions a hell of a 
> lot easier since it will no longer be necessary to monkey the php.ini file to 
> include them. At a minimum the parser needs to know that the import will not 
> be in the registry and instead it should look to the extensions directory, 
> hence the lead @. Speaking of, having the extension directory location be a 
> directive of php.mod makes sense here.  Each module can have its own 
> extension directory, but if this is kept within the project instead of 
> globally then web SAPIs definitely need to stay out of those directories.
> 
> Final thing to touch on is how the module namespaces behave. The export 
> statement is used to call out what is leaving the module - everything else is 
> private to that module. 
> 
> class A {}  // private
> export class B {}  // public
> 
> All the files of the package effectively have the same starting namespace - 
> whatever was declared in php.mod.  So it isn't necessary to repeat the 
> namespace on each file of the package. If a namespace is given, it will be a 
> sub-namespace
> 
> namespace tests;
> 
> export function foo() {}
> 
> Then in the importing file
> 
> import "./src/mymodule"
> use \mymodule\tests\foo
> 
> 
> Notice here that if there is no from clause everything in the module grafts 
> onto the symbol table.  Subsequent file loads need only use the use 
> statement. Exported variables however must be explicitly pulled because the 
> variable symbol table isn't affected by namespaces (if I recall correctly, 
> call me an idiot if I'm wrong).
> 
> The from clause is useful for permanently aliasing - if something is imported 
> under an alias it will remain under that alias. Continuing the prior example
> 
> import tests\foo as boo from "./src/mymodule";
> 
> boo()
> 
> That's enough to chew on I think.

I don't think it is wise to intertwine this concept of modules with namespaces 
like that, but I am replied out for the night. :-)

-Mike

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