The self-reproducing expression,
({&a.,":)40 123 38 97 46 44 34 58 41
({&a.,":)40 123 38 97 46 44 34 58 41
is an instance of a list of numbers that can auto-process itself (by putting
in front of itself its own representation according to the alphabet) since
40 123 38 97 46 44 34 58 41{a.
({&a.,":)
Other lists of numbers can auto-process themselves, for example,
a.i.'%'
37
%37
0.027027
We can even write a verb to test if a list of numbers can auto-process
itself; for example, an extension of the body of the self reproducing
expression (".@({&a.,":)) does the job,
(".@({&a.,":))37
0.027027
Other lists of numbers cannot auto-process themselves, for example,
a.i.'$:'
36 58
(".@({&a.,":))36 58
|stack error
| $:36 58
The testing verb itself has an associated list of numbers,
a.i.'(".@({&a.,":))'
40 34 46 64 40 123 38 97 46 44 34 58 41 41
and an interesting Turing question follows: Can this list of numbers
auto-process itself? Well, we can just find out... Hold on, apparently is
not that simple (hint: save your work first!)
(".@({&a.,":))40 34 46 64 40 123 38 97 46 44 34 58 41 41 NB. Beauty is in
the eye of the beholder.
> [mailto:[EMAIL PROTECTED] On Behalf Of Jose
> Mario Quintana
>
>
>
> The following is not one of the most concise Quine
> self-reproducing expression. Yet, it is a favorite of mine:
> quoteless with a Godelian body-genes pattern,
>
> ({&a.,":)40 123 38 97 46 44 34 58 41
>
...
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