This can almost be proved by combining Theorem 1 of Ben-Amram and Galil , where n steps on a RAM are simulated by O(n log n) steps on a pure Lisp machine, with an obvious simulation of n steps on an impure Lisp machine simulated by O(n) steps on a RAM.
THEOREM 4.1 There is an on-line symbolic impure Lisp machine M such that any simulation of M by a pure Lisp machine M[prime] requires (for some input sequences) [Omega](n log n) steps by M[prime] to produce the outputs that are produced during the first n steps by M.
The Lisp Machine
developers did nothing so impressive.
On a Lisp machine this write barrier, as it is called, is implemented efficiently in hardware.
* Common Windows, which has its roots in the Xerox Lisp machine windowing system, is a simple but effective windowing system that is becoming somewhat outdated.
have not provided the types of interface required here.
I was also asked to consult on the joint project between Xerox and Quintus Computer Systems to build Xerox Quintus Prolog, a microcode implementation of Prolog on the Xerox Lisp Machines
, based on the Warren Abstract Machine (WAM).
In 1982, Symbolics and LMI marketed "LISP machines" optimized for the western AI language of choice.
In the late 1980s, LISP machines had ceased to provide a significant advantage over LISP running on less expensive platforms, notably the Mac.
Companies showing LISP machines
, knowledge-based programming environments, and AI solutions occupied large booths at jammed AI conferences.
Although prices are coming down, hardware (Lisp machines
) and software are still expensive.
and general purpose scientific and engineering workstations are complicated minicomputers requiring months of diligent training.