New lib/datalog/api.sx: dl-program-data facts rules takes SX data
lists. Rules accept either dict form or list form using <- as the
rule arrow (since SX parses :- as a keyword). dl-rule constructor
for the dict shape. dl-assert! adds a fact and re-saturates;
dl-retract! drops EDB matches, wipes all rule-headed IDB
relations, and re-saturates from scratch — simplest correct
semantics until provenance tracking arrives.
9 API tests cover ancestor closure via data, dict-rule form,
dl-rule constructor, incremental assert/retract, cyclic-graph
reach, assert into empty, fact-style rule (no arrow), dict
passthrough.
giles
ce603e9879