[Racket announcement] Today's DrRacket problem

From: Matthias Felleisen (matthias at ccs.neu.edu)
Date: Mon Mar 26 10:45:27 EDT 2012

Dear Racket users, 

Many of you noticed that DrRacket v5.2.1 refused to launch today,
March 26.  We sincerely apologize for this inconvenience.

The problem is due to a so-called "Easter egg", which is a visual
surprise that one developer builds into the code for the others and
our users -- a tradition going back to the early days of our
project. The bug affects only DrRacket, no other Racket software.

As far as version 5.2.1 is concerned, the bug will disappear tomorrow,
but it will return later this year.  For the upcoming release -- due
out before the next "easter egg" date -- we will either install much
more reliable test methods for the Easter eggs or we will remove them

We intend to make a fixed version of 5.2.1 available later today. In
the meantime, we offer the following workarounds for the DrRacket bug:

* Revert to version 5.2:


* In your current installation of 5.2.1, navigate to the following

     collects -> drracket -> private 

  remove the file


  and replace it with the corrected copy at


* For those of you with commandline tool experience, download a Racket
  patch file from


  navigate in your shell to the folder with the 5.2.1 executables, and
  install the patch with

    ./raco setup -A ....

  where .... specifies a path to the downloaded file.

As much as we prepare and test these Easter eggs, software obeys only
one law: what can go wrong will go wrong eventually. We definitely
should have been more careful.

Once again, we regret any problems we caused you today

-- Matthias Felleisen, for PLT 

Posted on the announce mailing list.