How to create hygienic environments?

[Michael Tiedtke]

Does anyone know how I to create empty environments in Guile Scheme 
(preferably 1.8)?
The task at hand is well known: the user of an text editor can input 
complex commands with parameters (a little bit like in Emacs). Now I 
would like to /read/ these commands as single procedure calls with its 
parameters as an s-expression. But then how do I /eval/uate it in a 
special environment where only the editor commands are available by default?
The /(null-environment 5)/ gives me an empty environment but how should 
I insert the editor commands? Last time I checked (that was about some 
years ago when I didn't really need it) I found some C only routines but 
maybe I mixed them up with the UNIX process environment (variables).
How do I create a hygienic algorithmic text editor language within the 
Algorithmic Language Scheme?
Perhaps it's even better to give access to the usual Guile top level 
environment ...