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Environment-objects don't exist in CL according to manual



Prodded by all this recent discussion about whether environments have
dynamic or indefinite extent, how one might obtain an
environment-object so as to pass it as optional argument to EVAL, what
kinds of info might be captured in such an object, I looked in the
index to the CL manual to see what the manual said about environments.
The answer, if I can believe the index, is that CL has no such things
as environment objects. There are only two mentions of "environment"
in the index: one referring to a general statement that special
structures in CL allow the programmer to organize a program, some
having to do with flow of control (control structures) and others
controlling access to variables (environment structures); the other
referring to LISP funcitons to query the system regarding such matters
as time-of-day or CPU-ID. Neither has anything to do with the topic
that seems to be under discussion recently.

Is this recent discussion utter nonsense (referring to some local
extension to CL rather than to CL itself), or is the index grossly
deficient in this topic? If the latter, can somebody supply me/us with
a list of pages where environment objects are discussed in the CL
manual? If the former, there seems to be no need to introduce the
topic; if environment-objects can't be passed to functions, there's no
need to worry about how to create them or what aspects of the
environment they might encapsulate if they could be created.