“Yields circularity when preceded by its quotation” …

yields circularity when preceded by its quotation.

Today’s post takes us on a little circular tour of the internet, starting with:

Grumpy Old Programmer (Mike Woodhouse) who returns from a long holiday from blogging to publish a nice little routine to generate a circular optical illusion:

He refers to the (very compact) code as being “golfed”, with a link to Programming Puzzles and Golf code, where I was introduced to the idea of a computer programming “quine”, that is computer code, which when run reproduces itself in full.  A very brief example in Python is shown below (line 1 is the code, the second line the output).

But I can do better than that, using the “Classic” Lotus 123 macro script.  If we enter in cell B1:  /C~{D}~
and give it a range name, starting with a backslash, say \Q, then press CtrlQ, in cell B2 appears: /C~{D}~.

We have a 7 character long quine.  Now if we add a {D} on the end, the code now copies itself down a row, then moves down to the next line, where it reads and carries out any code it finds there, resulting in a second copy, and a second move down, and so on, until the end of the universe, which in the case of this no longer brief computer code, is row 65536 of the spreadsheet:

All this talk of Quine and quining reminded me of Douglas Hofstadter, and a search on his name led me to xkcd 917:

Which completes the circular tour with a link back to this blog, wherein a work of Douglas Hofstadter is reduced to not 6 words, but a single two letter word:

MU.

Hope you enjoyed the trip.