How to throw a PHP Exception from Go

[IndraGunawan]

I've been reading https://frankenphp.dev/docs/extensions/ page and I am trying to build a PHP extension entirely in Go. So far, the type mapping for strings and integers works great.

However, I can't find a way to make a function throw a PHP Exception when something goes wrong in the Go logic.

If a Go function fails, I want to handle it with a standard PHP try/catch block:

try {
    repeat_this('hello', -1); 
} catch (Exception $e) {
    echo "Caught: " . $e->getMessage(); // Should show the error from Go
}

Is there a way to trigger a PHP exception from within the Go function?

[withinboredom]

I don't think there is one built-in. But if you don't mind writing some C, it's not hard to do. Basically, on the C-side, you need a thread-local "current_exception" variable, then a way to write to it from Go when you have an error, then check that variable any time you return from go to clear and throw the exception, if it is set.

It hurts performance to do it generally, but that's the pattern I've been using on my project.

[alexandre-daubois]

Is there a way to trigger a PHP exception from within the Go function?

At this time, there's no dedicated "function" or public API to do so like there is for type juggling. Maybe this could be a nice addition, or at least deserves a section in the docs if it's straightforward!