I moved the thread here as this project emerged from Hype Power Pack but got more involved. Hype Power Pack is still reasonably simple, and I will leave it on GitHub as is.
This thread will be released under a new name soon 
Next Update includes error handling for the Closure Compiler and some options for the compiler and unpacking of user written Hype functions. As I am busy with regular work, updates might slow down a bit, but there is certainly much more to come. Here is a sneak peak of something I just finished …
- The errors found by the Closure Compiler are added to your source (line numbers are adjusted accordingly)(1) and Closure Compiler errors offer some valuable insights.
- If code compilation fails, the uncompiled code is included giving you the full debugging capabilities you get from the regular error or when not using the Closure Compiler option.
- Hence, the line numbering and full regular error descriptions are usable to track errors stacks, as already possible since version 1.0.4. of Hype Power Pack.
1) I even made sure to get the indicator correct from the lineno and charno data provided by the compiler.
The error layout is modelled according to the online appspot version.
