🚀 go-pugleaf

On the model of SQL, one might expect that there would be
C/Fortran/Pascal/COBOL/PL/I/&c interfaces to Prolog which
looked roughly like

	%Prolog create :C cursor for ancestor(adam, :PERSON, :NGENERATIONS);
	%Prolog open :C;
	DO WHILE (MORE(C));
	    IF PERSON = 'C.J.Date' THEN DO;
		%Prolog abandon :C;
	        PUT SKIP LIST ('There are ', NGENERATIONS,
			       ' generations from Adam to ', PERSON);
	    END;
	END;
	%Prolog finish :C;

Of course, procedure calls might be used, but the "embedded-SQL" style
isn't really a matter of syntax.

Does anyone know of any working implementations of this idea, especially
ones predating 1987?

-- 
"A 7th class of programs, correct in every way, is believed to exist by a
few computer scientists.  However, no example could be found to include here."