angular build optimizer does not work with monaco editor

[wszgrcy]

monaco-editor version: 0.18.1
**Browser:chrome
**OS:win10

Steps or JS usage snippet reproducing the issue:
The problem in this issues
It's not my issues but I have the same with it.
error-demourl
When I run with ng serve the monaco has no bug
But When I run with ng serve --prod(production mode),the monaco has bug on Console

I think the bug belong to angular-cli or monaco ,but in angular-cli ,past few months, it's not fixed.So I hope monaco can see it and give a solution.

[alexdima]

This looks like it is an issue specific to @angular-devkit/build-optimizer --- angular/angular-cli#14033 . We can leave this issue here open for a while, but there is no code change planned on our side to address this...

[petermikitsh]

Angular appears to have no plans to change this behavior in the build optimizer. You need to turn off the build optimizer, or have the optimizer ignore Monaco.

However, if the error stems from not following best practices (e.g, object property access should be side-effect free), it could be worthwhile to explore changing Monaco so it plays nicely with uglifyjs. It could benefit the maintainability of Monaco, since developers working on Monaco could unintentionally assume those best practices are valid here.

Both sides present valid arguments. Angular shouldn't impose assumptions on third-party library code, but also making changes to conform to those fairly reasonable assumptions could be overall beneficial to maintainers.

[alexdima]

Ignoring the tree shaking optimization for the Monaco Editor sounds reasonable.

The Monaco Editor is shipped from "tree shaken" VS Code sources -- see here