rack/rack — pull request #381 by seamusabshere (2012-05-01 16:48:56+00:00)
Title: provide Rack::Request#update_param and #delete_param

Includes tests.

I needed in my own app and I saw people asking in Stack Overflow:

http://stackoverflow.com/questions/6046705/add-api-key-on-every-request-with-rack-middleware
http://stackoverflow.com/questions/5028958/rack-and-rack-request-form-vars-rack-request-form-hash

This would fix both problems, I think.