Let’s undo one of the human-input conveniences and normalize the factbase to contain only machine-readable codings.

Currently, arrows contain references to graphical objects. These references should actually be ids. These references are (human-readable) synonyms to (machine-readable) ids.

For example, as in part 4, we have facts like:

comp(id5, c).
arrow(id40, a41).
arrowBegin(a41, c_c).
arrowEnd(a41, [c_e_m]).

Firstly, we can create synonym facts, e.g.

comp(id5, c).
synonym(c, id5).

Then, we use the synonym facts to modify all arrowBegin facts, e.g.

arrowBegin(a41, c_c).
aBegin(a41, idYYY).

Then, we use the synonym facts to modify all arrowEnd facts, e.g.

arrowEnd(a41, [c_e_m]).
aEnd(a41, [idZZZ]).

N.B. Currently, we leave all of the facts in the factbase. There is no need to remove facts. Removing facts at this stage – without proof of needing to do so – is premature optimization (and uneccessary brain clutter).

We define gobject(ID). See q.pl

Since we specify the synonym in gobject definitions, the query for synonyms is straight-forward
synonym(ID,Synonym) :-


[A ‘nonArrowGobject’ is any gobject except arrows. See the code for further details.]

Creating a new aBegin fact consists of a compound query - print out an aBegin fact for every arrowBegin fact, replacing the synonym… (again, details elided, see code):

printAllABegin :-

Sanity Checks

I create gkind and tag queries and double-check by running queries and looking at the diagram (the code for transpilation in this example is meant to be done manually, so I would expect many bugs. We’ll see what I missed when we try to run this stuff.)

For example, we double-check the arrow with two receivers:

?- consult(fb).

?- consult(q).

?- printAllAEnd.

?- tag(id62,Tag).
Tag = e_e_l ;

(which appears to coincide with what is on the diagram).