In what context is `jupyter lab --watch` necessary in order to see updates?

JupyterLab
1

The documentation states, “To update the module, simply go to the extension directory and run jlpm build again. Since you used the --watch option when starting JupyterLab, you just have to refresh the JupyterLab website in the browser and should see in the browser console”

I find that this works fine by just running jlpm run build, and running jupyter lab without the --watch argument.

I’m able to get everything to build just fine. However, I am confused about exactly which commands are necessary for which desired results in the development workflow.

References: extension-examples/basics/hello-world at master · jupyterlab/extension-examples · GitHub

2

For prebuilt extensions, the --watch part of jupyter lab --watch is no longer required: you can just rebuild the extension (jlpm run build) and refresh the browser page and the changes will be picked up.

For source extensions, jupyter lab --watch is needed so that JupyterLab can rebuild itself to incorporate the changes in the extension.

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