/** Partially evaluate the right-hand side and the conditions for each rule. */
private static Definition evaluateDefinition(TermContext termContext) {
Definition definition = termContext.global().getDefinition();
/* replace the unevaluated rules defining functions with their partially evaluated counterparts */
ArrayList<Rule> partiallyEvaluatedRules = new ArrayList<>();
/* iterate until a fixpoint is reached, because the evaluation with functions uses Term#substituteAndEvalaute */
while (true) {
boolean change = false;
partiallyEvaluatedRules.clear();
for (Rule rule :
Iterables.concat(
definition.functionRules().values(), definition.anywhereRules().values())) {
Rule freshRule = rule.getFreshRule(termContext);
Rule evaluatedRule = evaluateRule(freshRule, termContext);
partiallyEvaluatedRules.add(evaluatedRule);
if (!evaluatedRule.equals(freshRule)) {
change = true;
}
}
if (!change) {
break;
}
definition.functionRules().clear();
definition.anywhereRules().clear();
definition.addRuleCollection(partiallyEvaluatedRules);
}
/* replace the unevaluated rules and macros with their partially evaluated counterparts */
partiallyEvaluatedRules.clear();
Iterable<Rule> rules =
Iterables.concat(
definition.rules(),
definition.macros(),
definition.patternRules().values(),
definition.patternFoldingRules());
for (Rule rule : rules) {
partiallyEvaluatedRules.add(evaluateRule(rule, termContext));
}
definition.rules().clear();
definition.macros().clear();
definition.patternRules().clear();
definition.patternFoldingRules().clear();
definition.addRuleCollection(partiallyEvaluatedRules);
return definition;
}
