[net.lang.prolog] Corrections about Prolog Systems

bts (12/16/82)

Re:
	Title: Prolog Systems Available
	Article-I.D.: cwruecmp.338

Some corrections to your list of Prolog systems:

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Name:		DEC-10/20 Prolog
Version:	3.3X
Source/OS:	Prolog+Macro-10; TOPS-10 & TOPS-20
Availability:	For research and teaching only
Cost:		$70 handling charge
Status:		Semi-active
Contact:	David Warren
		AI Center
		SRI International
		333 Ravenswood Ave.
		Menlo Park CA 94025
		ARPANET: WARREN@SRI-AI
Notes: this version is vastly improved in comparison with
       the one mentioned in the earlier note: an incremental
       compiler intergrated with the interpreter producing
       tail-recursion optimized code, an interactive debugger
       and execution stepper for interpreted code, many other
       goodies.

-------------------------------------------------------------------------

Name:		CProlog
Version:	1.1
Features:	interpreter, no compiler
Cost:		100 pounds
Notes:		Nothing to do with Unix Prolog from DAI. CProlog
		is internally rather similar to DEC-10/20 Prolog
		(less the compiler), and uses the data representation
		scheme known as structure sharing; DAI Unix Prolog
		uses another very different data representation
		system, copy-on-use (also known as non-structure-sharing).

--------------------------------------------------------------------------

Name:		MProlog
Source:		Don't think CDL2 is available in 100s of different
		machines; porting CDL2 (or the system-dependent of
		MProlog) to a new machine is non-trivial. As far
		as I know, it is only available under IBM VMS,
		Siemens and VAX/VMS.
Note:		CDL2 was designed by Koster and others in Berlin;
		I understand the CDL2 system development system
		is available from a software house there.

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Name:		IC-PROLOG
Source:		Pascal
Notes:		IC-PROLOG is DEFINITELY NOT patterned after DEC-10
		Prolog: its systax is different, it has very different
		execution mechanisms and system predicates. It is
		a system to experiment with more flexible execution
		mechanisms, not a system to run large programs fast.

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		Fernando Pereira (pereira@sri-ai)
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