notify called synchronously

[rtfeldman]

Just following the error message's instructions... 😉

Uncaught Error: Error sending to port 'loadDoc': 
invalid input, expecting JSString but got undefined
elm-runtime.js:1741

Uncaught Error: The notify function has been called synchronously!
This can lead to frames being dropped.
Definitely report this to <https://github.com/elm-lang/Elm/issues>
elm-runtime.js:9143

notify elm-runtime.js:9143
(anonymous function) elm-runtime.js:1744
Uncaught Error: The notify function has been called synchronously!
This can lead to frames being dropped.
Definitely report this to <https://github.com/elm-lang/Elm/issues>

Steps to reproduce:

1. Check out this commit in dreamwriter-elm: rtfeldman/dreamwriter@34f8d9d
2. Install Dreamwriter's dependencies with npm install
3. Run rm -rf node_modules/grunt-elm/test after doing npm install to work around a grunt-elm bug I haven't fixed yet (Don't accidentally build grunt-elm's tests rtfeldman/grunt-elm#3)
4. Run npm install grunt-cli if you don't already have the Grunt CLI installed globally.
5. Run grunt to build Dreamwriter
6. go to localhost:8000 and click the new button in the upper-left
7. Check the console!

This is definitely caused by my having not finished correctly implementing the JS port yet, but it does consistently reproduce an error that urged me to report it, so...here we are. 😸

[evancz]

This error is typically only seen by internal APIs. It's a warning for when we start an event flowing through the signal graph while already partially through the graph. The result is that things get out of sync and the previous frame will "jump ahead" of the one in front.

I am not sure why you'd be seeing it using ports though. I would guess that the locking mechanism we are using is rather coarse grained at the moment or something. In any case you can get around this with a setTimeout for now, but that's definitely not the real answer here.

[maxsnew]

I get this error any time I write a program that crashes.

[rtfeldman]

Yeah it went away as soon as I finished fixing my ports stuff...just reporting it here in case being able to reproduce it proves useful for runtime development.

[mgold]

Sounds like an opportunity to check ports and provide a better error message?

[evancz]

I don't think there's enough to go on here, so I am going to close this for now. If we can narrow this down to a more specific issue or recommendation, let's open a new issue.