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In Common Lisp, what is printed representation?

I use SBCL, emacs, slime and quicklisp to install various packages.

I instantiate and run the hunchentoot acceptor, for example,

CL-USER> (hunchentoot:start (make-instance 'hunchentoot:acceptor :port 4242))
#<HUNCHENTOOT:ACCEPTOR (host *, port 4242)>

I am testing by opening a browser on port 4242 and it works great.

Then, to stop it, I can copy the printed view and issue the command like this:

CL-USER> (hunchentoot:stop #<HUNCHENTOOT:ACCEPTOR (host *, port 4242)>)
#<HUNCHENTOOT:ACCEPTOR (host *, port 4242)>

This only works with the printed view returned by the corresponding start.

This is amazing for me. I thought that the printed view was simply textual, presumably because the object itself could not be displayed. As such, I thought it was pretty neat that hunchentoot: stop could use a text string to search for an object. But then with a lot of experimentation, I noticed that I had to use a printed representation corresponding to the beginning, and not just one. I also notice that when I hover over a printed image, it selects the entire segment. So this is not text at all, but an object that is actually in the REPL, and I can use it.

, , , , , REPL. ? , , . .

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"". . SLIME, Presentations.

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BBN (Zdybel, et al., Information Presentation System, 1981), Symbolics Lisp Machine Common Lisp Interface Manager, . .

SLIME REPL.

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SLIME "". , " " Lisp, : . SLIME , #<...> - Lisp Machine...

:

CL-USER> (defvar *server* (hunchentoot:start (make-instance 'hunchentoot:easy-acceptor :port 4242)))
*server*
CL-USER> (hunchentoot:stop *server*)
#<HUNCHENTOOT:ACCEPTOR (host *, port 4242)>
+7

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