Mikalai <mbirukou@yahoo.com> wrote:
+---------------
| Can you help me with the following.
| I have a object. I do not know neither the number of slots
| nor names of the slots. Is there a way to access them?
+---------------

In addition to other answers you've gotten, if you're sitting
at a REPL don't forget the simpleminded use of DESCRIBE:

    > (describe random-object-1)
    #<Closure Over Function "LAMBDA (X)" {4893B8E1}> is function.
    Arguments:
      There are no arguments.
    Its defined argument types are:
      NIL
    Its result type is:
      LIST
    On Sunday, 3/26/06 07:39:32 pm PST it was compiled from:
    #(#'(LAMBDA # #))
    Its closure environment is:
    0: 56
    1: 34
    2: 12
    > (describe random-object-2)
    #<Stream for file "/u/rpw3/foo.log"> is a structure of type FD-STREAM.
    IN-BUFFER: NIL.
    IN-INDEX: 512.
    IN: #<Function LISP::INPUT-CHARACTER {101BB3F9}>.
    BIN: #<Function LISP::ILL-BIN {10060F41}>.
    N-BIN: #<Function LISP::FD-STREAM-READ-N-BYTES {10169299}>.
    OUT: #<Function LISP::ILL-OUT {1011D601}>.
    BOUT: #<Function LISP::ILL-BOUT {1006E481}>.
    SOUT: #<Function LISP::ILL-OUT {1011D601}>.
    MISC: #<Function LISP::FD-STREAM-MISC-ROUTINE {100C3439}>.
    NAME: "file \"/u/rpw3/foo.log\"".
    FILE: "/u/rpw3/foo.log".
    ORIGINAL: NIL.
    DELETE-ORIGINAL: NIL.
    ELEMENT-SIZE: 1.
    ELEMENT-TYPE: CHARACTER.
    FD: 6.
    BUFFERING: :FULL.
    CHAR-POS: NIL.
    LISTEN: NIL.
    UNREAD: NIL.
    IBUF-SAP: #.(SYSTEM:INT-SAP #x28137000).
    IBUF-LENGTH: 4096.
    IBUF-HEAD: 0.
    IBUF-TAIL: 0.
    OBUF-SAP: NIL.
    OBUF-LENGTH: NIL.
    OBUF-TAIL: 0.
    OUTPUT-LATER: NIL.
    HANDLER: NIL.
    TIMEOUT: NIL.
    PATHNAME: #p"/u/rpw3/foo.log".
    > 

Yes, DESCRIBE is implementation-specific, and some implementations
will tell you more or less than others. But it's a useful tool
when doing interactive exploration.

Ditto INSPECT...


-Rob

-----
Rob Warnock			<rpw3@rpw3.org>
627 26th Avenue			<URL:http://rpw3.org/>
San Mateo, CA 94403		(650)572-2607