Hi! This might help: (run it before your code)

(setf (cdr (assoc '*PRINT-RIGHT-MARGIN*
swank:*backtrace-printer-bindings*)) 500)

If 500 is not enough, try greater value.

2017-08-02 12:31 GMT+03:00, Jim Newton <jimka.issy@gmail.com>:
> Can someone tell me how I can grab a lisp expression from a stack trace, as
> in copy it in emacs so I can re-paste and potentially edit it in the repl?
>
> When I move the cursor to the line, the entire text displays in the echo
> area at the bottom of the emacs window,  but when use use CNT-E to move to
> the end of the line, the line has been truncated and i see "..".  I'd like
> to copy/paste the un-truncated line.
>
> I'm attaching images of what I see.
>
> Kind regards
> Jim
>