Subject: bug#6893: evaluating `'#'(lambda (b) b)8 ; => 8 with `eval-last-sexp' "C-x C-e" in `emacs-lisp-mode'

From: MON KEY <[email-masked]>
Date: Sat, 21 Aug 2010 17:55:03 -0400

Interactive invocation of `eval-last-sexp' (e.g. "C-x C-e" ) in
Emacs-lisp mode buffer for this form:

 `'#'(lambda (b) b)8
 ;=> 8

`eval-last-sexp' for this makes (some) sense:

 `'#'(lambda (b) b)
 ;=> (quote (function (lambda (b) b)))

And so, presumably the above is equivalent to:

 (eval '(list 'quote '(function (lambda (b) b))))
 ;=> (quote (function (lambda (b) b)))

But what is the equivalent form which would explain the results for
following:

 `'#'(lambda (b) b)8
 ;=> 8

Surely it isn't this:

 (funcall (eval (eval (eval '(list 'quote '(function (lambda (b) b)))))) 8)
 ;=> 8

If it is, then why is eval'ing the same `'#'(lambda (b) b)8 form with
`eval-expression' (e.g. "M-:") met with the message:

 "Trailing garbage following expression"

Likewise, giving `eval-expression' this form lands me in the debugger:

 (`'#'(lambda (b) b) 8)

 ;=> Debugger entered--Lisp error:
     (wrong-number-of-arguments #[(structure) "\301!A\207"
                                  [structure backquote-process] 2 1720176] 2)

Reproducable on 23.2 with emacs -Q

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