misc, A very basic language in runes? :-)

see

http://www.jbum.com/idt/r.html

Cute, but not Turing-complete, since there is no subtraction and no way to
represent negative numbers, nor are there enough logical operators. You
need negation and at least ">=" in addition to equality. Using the same
sign for assignment and equality is no problem; FORTRAN and most BASIC
dialects still do it. Of course, it wouldn't be difficult to map "AND",
"OR" and "NOT" to arbitrary runes, and to provide subtraction and
arithmetic negation. The real bitch is the use of only one parenthesis
sign. That prohibits nested parentheses, which would lead to some
excruciatingly ugly code.

What's the current record holder for smallest Turing-complete language,
anyway? Brainfuck comes to mind, but I dimly recall an even smaller
language, designed to run in 256 bytes (No, that's not a typo!) of RAM on
an 8080.

If you can prove R to be Brainfuck complete then R will be proved Turing
complete.


BitChanger and P'' are two four instruction Turing complete languages.
P'' originated in 1963.

http://esolangs.org/wiki/BitChanger
http://en.wikipedia.org/wiki/P_Prime_Prime

A possible 3 instruction language is documented on the Brainfuck
minimalisation page.
http://esolangs.org/wiki/BF_instruction_minimalization

There is also the OISC (One Instruction Set Computer) which is Turing
complete and only has one instruction.

http://www.cs.uiowa.edu/ ~jones/arch/risc/

Regards,
Jon
--
http://jonripley.com/

Thanks for the information on tiny languages - fascinating.

You can join the Druidical research association - Osric the Stoat is
worth investigating.

I stumbled on Druidical R whilst searching for material on the
statistical language "R".

I have some doubts about calling it "Druidical" - I have a vague
inkling that the Druids were Celtic and Runes are associated with
Vikings (not Celtic). Anyway...

Lance

Yup, Runes are a new-fangled innovation of those quiche-eating Vikings.
Real Druids were well known for Never Writing Anything Down If it Could
Be Committed To Memory. And since Real Druids all had Very Good
memories they never needed to write anything down. Hence the lack of
manuals for Stonehenge, <grin>

Cheers

Derek