Oct 10 2015

Angular 2 alpha 38-or-so error finding Subject.js

Published by at 8:31 pm under Technology   

Here’s a tip for the intrepid out there who are following the Angular 2 alphas. It has been somewhat harrowing, as alpha software tends to be. Here’s a problem I encountered today, and could not find an obvious answer anywhere on the Internet, therefore this post.

Here’s a critical piece of background, I have been using JSPM to manage dependencies in my Angular 2 work. I am using an alpha package manager with an alpha module loader to load an alpha framework and it’s mostly-alpha dependencies. Realistically it is surprising that it sometimes works at all.

I made the mistake(?) of falling behind a couple of weeks in the alphas – rather than updating one at a time I leapt directly from 37 to 40. With a bit of experimentation I found that breakage occurs starting with Alpha 38, and elaborate error failing to load a file Subject.js.

After reading numerous websites, Angular alpha diffs, and so on, it appears that this is related to the transition recently to “RxNext”, the upcoming next version of reactive extensions.  The new dependency is visible in the top level package.json, for reasons unknown to me JSPM did not notice this and bring it in. Fortunately all of the sulfa software coordinated enough to fix the problem with a single command:

All of the Alpha stuff, that’s just life in your working with software on the edge. The one piece of this thing that I am a bit unhappy with is the name of the package mentioned above. This is the first NPM package I’ve encountered that begins with or otherwise includes a special character. I didn’t even know that was allowable, and I hope it does not become common practice.


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