Ask for help: any previous work that has context-like type expressions?

Dear types researchers,

I am currently writing a paper on types for the ambient calculus.
In my type system, a context-like type expression is adopted to make
the system concise and easy-to-prove.  To my knowledge, no previous
work on types for the ambient calculus has such construction.
I wonder is there any existing type system in other fields that has
context-like type expressions?

To go a little further on my work, please read the following.
A process is what we want to type.  A typable process will have a type,
denoted by T.  A process may has the form M.P, where M is some action
and P is some other process.  Suppose M has type W and P has type T.
To derive the type of M.P, T', one way is to define some function F, which
calculates T' from W and T.  Another way is to let W itself to be some
function, when given T, results T'.  When F is difficult to find, the
second way is prefered. In this case, W could be regarded as a type context.

For those interested, a 5-page draft is avaliable at:

Best regards,


Xudong Guan                                               PhD Candidate
Email: guan-xd@cs.sjtu.edu.cn   Distributed Computing Technology Center
Tel:   +86-21-52581638 ext.17          Room 1105, Haoran Hitech Mansion
Visit my mobile ambient page at:               Shanghai Jiao Tong Univ.
http://go.163.com/~mobileambient/               Shanghai, China, 200030