axaris@acsu.Buffalo.EDU (vassilios e axaris) (02/09/90)
Hello, I need a clarification on the following put instruction please. I shall use D.H.Warren's notation from his paper An Abstract Prolog Instruction Set. put_variable Xn|Yn,Ai : For Yn the paper lists the following assignment: Ai := Yn := ref_to(Yn) For Xn it lists the following: Ai := Xn := next_term(H) := tag_ref(H) Question 1: For the Yn case, ref_to(Yn) puts in Ai a tagged reference or just the address of Yn without tag? Question 2: For the Xn case, Ai, and Xn get the current heap pointer converted to a tagged reference, or its raw value? Which is executed first? next_term or tag_ref. Compare this with the description of put_structure where it is stated the following: Ai := tag_struct(H) next_term(H) := F (the functor) I shall appreciate any kind of information. Thanks in advance, Vassilios E. Axaris SUNY Buffalo Computer Engineering.