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  1. (defparameter *my-readtable* (copy-readtable))
  2.  
  3. (let ((*readtable* *my-readtable*))
  4.   (set-dispatch-macro-character #\# #\. nil))
  5.  
  6. (defun safe-read ()
  7.   (let ((*readtable* *my-readtable*))
  8.     (read)))
  9.  
  10. (setf b (safe-read))
  11. (princ b))
Runtime error #stdin #stdout 0.03s 10792KB
comments (?)
stdin 
#.(progn (format t "Oh, exploitable!~%") '(+ 2 2))
stdout 
Standard output is empty
https://ideone.com/aIUUN
language:
Common Lisp (clisp 2.49.92)
created:
13 years ago
visibility:
public

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