> [EMAIL PROTECTED] On Behalf Of Boyko Bantchev
>
> On 5/16/07, June Kim <[EMAIL PROTECTED]> wrote:
> > My original ideas was printing only the codes on the T-shirt.
> >
> > However, displaying the result of the code together might be a good
idea,
> too.
>
> You can have both at once if you use a quine,
> such as http://www.nyx.net/~gthompso/self_j.txt
> (although this particular phrase hardly shows anything
> very interesting or distinguishing of J).
Josh's's above referenced expression is both, a J Quine (it displays
itself),
".a=.'''".a=.'',q,q,~a#~1+a=q=.39{a.'
".a=.'''".a=.'',q,q,~a#~1+a=q=.39{a.'
and a J (self-contained) self-reproducing expression ((-: ".) holds true for
the expression),
(-: ".) ".a=.'''".a=.'',q,q,~a#~1+a=q=.39{a.'
1
However, it does not exhibit J conciseness (which, to be fair, might not
have been a goal).
I often find entertaining, given an expression, to search for the shortest
equivalent expression, for example, the shortest (self-contained) expression
for:
0. A self-reproducing expression (SRE)
1. Quine
2. A self-reproducing expression that is also a Quine
My efforts follow bellow [spoiler alert!]:
0. The shortest SRE to type: ''
(-: ".) ''
1
If the tally of the expression is used as the metric then '' is also a
winner
# ''
0
together with its myriads of siblings (e.g., Roger's i.0 0
http://www.jsoftware.com/pipermail/general/2001-February/005378.html ).
1. Although Dan Bron's 0 (see, http://www.jsoftware.com/jwiki/Puzzles/Quine
), or any of its siblings, is short enough; I would argue that an empty line
is, clearly, the shortest Quine:
The above J Quine is a testament of J conciseness compared to the other
solutions in http://www.nyx.net/~gthompso/quine.htm . I have used, and will
use, continuously this handy multi-purpose program in almost every J
session. One can find almost anywhere T-shirts that display it in the front
or back (or both) and have been wearing them since I was a baby.
2. Notwithstanding "emptiness is enlightenment" I am still puzzled about the
shortest self-reproducing expression that is also a Quine (i.e., the
shortest non-empty SRE?). My best effort (and I am giving up) is,
(,~,2#{:)'(,~,2#{:)'''
(,~,2#{:)'(,~,2#{:)'''
(-: ".) (,~,2#{:)'(,~,2#{:)'''
1
# (,~,2#{:)'(,~,2#{:)'''
22
which follows the pattern,
(,{:)^:2,~'expression'''
expression'expression'''
favored by Andrew Nikitin (see, the link above).
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