simonbo

simonbo

Modern Front-End Development for Rails - Webpacker and Unexpected token errors

Hello,

While trying to run the code examples from the book I always encounter the same issues that seem to be caused, maybe among other potential suspects, by webpacker.

I mostly get Unexpected token errors when webpacker tries to compile. It seems that Typescript isn’t well parsed.

By following some of the instructions described in webpacker’s README I managed sometimes before the use of Stimulus and React in the book to make it works. However once both frameworks present, I did not find my way through all those errors, to be honest.

So at this point, I can’t move forward in the book it became quite a struggle to fix here and there potential versions conflicts.

Would not it be interesting to freeze the versions of some gems/library in the Gemfile and the package.json?

Also before trying to run anything in a project directory, yarn always asks to proceed to do an integrity check, a bundle exec rails whatever can’t be run until it’s done. I don’t know if it can also play in upgrading automatically the versions that aren’t locked and thus maybe cause some issues later on.

error Couldn't find an integrity file                                                                                                     
error Found 1 errors.                                                                                                                     


========================================
  Your Yarn packages are out of date!
  Please run `yarn install --check-files` to update.
========================================


To disable this check, please change `check_yarn_integrity`
to `false` in your webpacker config file (config/webpacker.yml).


yarn check v1.22.4
info Visit https://yarnpkg.com/en/docs/cli/check for documentation about this command.

Thanks for the help, I really enjoy the book and would love to move forward through the practical aspect. :slight_smile:

Simon

Most Liked

noelrappin

noelrappin

Author of Modern Front-End Development for Rails

So, there are some versioning issues here. My plan has been to wait until the book goes final to lock the versions in the source code – it makes it easier for me to keep up while the book is in progress.

There are issues with Webpacker 5.1 and the Stimulus controllers (see https://github.com/stimulusjs/stimulus/issues/303), and I haven’t incorporated that fix into the book yet, so I’d try fixing Webpacker to ~5.0 and see if that helps.

Where Next?

Popular Pragmatic Bookshelf topics Top

jon
Some minor things in the paper edition that says “3 2020” on the title page verso, not mentioned in the book’s errata online: p. 186 But...
New
jesse050717
Title: Web Development with Clojure, Third Edition, pg 116 Hi - I just started chapter 5 and I am stuck on page 116 while trying to star...
New
yulkin
your book suggests to use Image.toByteData() to convert image to bytes, however I get the following error: "the getter ‘toByteData’ isn’t...
New
fynn
This is as much a suggestion as a question, as a note for others. Locally the SGP30 wasn’t available, so I ordered a SGP40. On page 53, ...
New
nicoatridge
Hi, I have just acquired Michael Fazio’s “Kotlin and Android Development” to learn about game programming for Android. I have a game in p...
New
jskubick
I found an issue in Chapter 7 regarding android:backgroundTint vs app:backgroundTint. How to replicate: load chapter-7 from zipfile i...
New
taguniversalmachine
Hi, I am getting an error I cannot figure out on my test. I have what I think is the exact code from the book, other than I changed “us...
New
mcpierce
@mfazio23 I’ve applied the changes from Chapter 5 of the book and everything builds correctly and runs. But, when I try to start a game,...
New
roadbike
From page 13: On Python 3.7, you can install the libraries with pip by running these commands inside a Python venv using Visual Studio ...
New
dachristenson
I’ve got to the end of Ch. 11, and the app runs, with all tabs displaying what they should – at first. After switching around between St...
New

Other popular topics Top

New
PragmaticBookshelf
Learn from the award-winning programming series that inspired the Elixir language, and go on a step-by-step journey through the most impo...
New
dimitarvp
Small essay with thoughts on macOS vs. Linux: I know @Exadra37 is just waiting around the corner to scream at me “I TOLD YOU SO!!!” but I...
New
PragmaticBookshelf
Build highly interactive applications without ever leaving Elixir, the way the experts do. Let LiveView take care of performance, scalabi...
New
AstonJ
We’ve talked about his book briefly here but it is quickly becoming obsolete - so he’s decided to create a series of 7 podcasts, the firs...
New
PragmaticBookshelf
Build efficient applications that exploit the unique benefits of a pure functional language, learning from an engineer who uses Haskell t...
New
PragmaticBookshelf
Programming Ruby is the most complete book on Ruby, covering both the language itself and the standard library as well as commonly used t...
New
New
First poster: AstonJ
Jan | Rethink the Computer. Jan turns your computer into an AI machine by running LLMs locally on your computer. It’s a privacy-focus, l...
New
sir.laksmana_wenk
I’m able to do the “artistic” part of game-development; character designing/modeling, music, environment modeling, etc. However, I don’t...
New

Sub Categories: