This is a robust self-printing program written in Ruby. It works even if you delete one character anywhere from the code.
How to play
rquine.rb and check if the output is equal to the original code:
$ ruby rquine.rb > rquine2.rb $ diff rquine.rb rquine2.rb
Prepare a script that deletes one character randomly:
$ cat mutate.rb src = ARGF.read src[rand(src.size), 1] = "" print src
Generate a broken program by deleting one character from
$ ruby mutate.rb rquine.rb > broken.rb
Run the broken program:
$ ruby broken.rb > rquine2.rb
You will see the output exactly equal to the original code:
$ diff rquine.rb rquine2.rb
- Perl version (attributed to Shinichiro Hamaji)
Copyright (c) 2014 Yusuke Endoh (@mametter), @hirekoke
Permission is hereby granted, free of charge, to any person obtaining a copy of this software and associated documentation files (the "Software"), to deal in the Software without restriction, including without limitation the rights to use, copy, modify, merge, publish, distribute, sublicense, and/or sell copies of the Software, and to permit persons to whom the Software is furnished to do so, subject to the following conditions:
The above copyright notice and this permission notice shall be included in all copies or substantial portions of the Software.
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