Generate externs files for external libraries

[vjpr]

A service to generate externs files for libraries.

1. Enter an external javascript file
2. Create a basic externs file
3. Run Compiler against user's codebase
4. Filter all warnings related to this library
5. Present user with snippets of code where the errors
6. If the errors are obvious like incorrect number of arguments, a button is provided to allow the user to make an argument optional - this is a common issue.

Existing work

http://www.joshuagranick.com/blog/?p=574
http://blogs.missouristate.edu/web/2010/11/02/jquery-extern-generator-for-closure-compiler/
https://github.com/robert-stuttaford/Closure-Script-Boilerplate
http://blog.dotnetwise.com/2009/11/closure-compiler-externs-extractor.html