Re: Low-level vs. High-level programming (was My First Computer)

["Randy McLaughlin" <randy@nospam.com>]

"Kelly Hall" <hall@priest.com> wrote in message
news:LxQJa.639$Yf2.58845238@newssvr15.news.prodigy.com...
>
> "Randy McLaughlin" <randy@nospam.com> wrote in message
> news:VUPJa.3368$QC5.2609@fe02.atl2.webusenet.com...
> > It similar to the chicken and the egg problem but it's not.  The Turing
> > engine defines what is required to be a particular type of machine.
That
> is
> > not related to what language it takes to program such a machine.  The
main
> > definition it had on programming was that the program was stored (on
tape
> > originally vs. hard-wired contemporaries).
>
> Two problems with what you say:
>
> The concept of Turing machines dates from 1936, before the first digital
> computers were built.  They were proposed to explore the meaning of
> computation, which is (to me) the heart of what one uses a 'computer
> programming language' to do.
>
> In a Turing machine, the tape does *not* store the program but only
symbols
> from an arbitrary set of symbols.
>
> http://plato.stanford.edu/entries/turing-machine/
>
> A useful feature of Turing machines is that they are powerful enough to
> describe themselves, leading to a Turing machine that can emulate another
> Turing machine - nested Turing machine, analogous to a CPU ISA emulating a
> second ISA (does P-code or JVM ring a bell?).
>
> Kelly

We are both slightly off target.  The Turing machine is still not the
"program" and p-code is not a virtual machine.  The virtual machine you are
trying to name is p-system, p-code was the code the virtual machine ran.