the meaning of #,

[AS%hp-labs.csnet@csnet-relay.arpa]

I am having a lot of trouble understanding the intended meaning of "#," in
compiled code.  I find it hard to believe that it is really intended to be
like "#.", as the manual implies.  In particular, the result of "#." in a form
becomes PART OF the form.  Thus, for example, you can do (DEFMACRO FOO
#.(MUMBLE) ...) and the result of invoking MUMBLE is used as the parameter
list to DEFMACRO.  Similarly, if I say (SETQ X #.(MUMBLE)) and MUMBLE returns
a list, then the list will be evaluated.  Is the intent that "#," can be used
this way (in compiled code), or can it be used only within quoted structures?
Implementors: How have you implemented "#,"?  Are there are restrictions on its
use?  If so, can they be stated clearly?

Thank you.
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