private void RunInferenceRulesOn(ClueId next)
{
if (_clueErrors[next].Any())
{
// If it errored out, we'll only be making it worse
return;
}
var targets = (new[] { next }.Concat(_clueDependsOn[next])).ToArray(); // 0 is always the next, 1 and on are its dependencies
foreach (var t in targets)
{
if (_clueErrors[t].Any())
{
// TODO: We can't really deduce anything
_clueErrors[next].Add(new InferenceError($"depended-on clue had an error: {t}"));
}
}
if (_clueErrors[next].Any())
{
// If it errored out, we'll only be making it worse
return;
}
foreach (var rule in _rules)
{
var tools = new Tools(this, targets);
rule(tools);
if (tools.Error != null)
{
if (tools.PreconditionsSatisfied)
{
_clueErrors[next].Add(tools.Error); // if one inference rule failed, others surely will too!
return;
}
// it's fine, that rule just doesn't apply here apparently
continue;
}
for (var i = 0; i < targets.Length; i++)
{
var clue = targets[i];
var oldType = _clueBestKnownType[clue];
var newType = free.Of(tools.Instantiate(i));
if (oldType.Equivalent(newType))
{
continue;
}
// if we're updating to a genuinely new type, rerun rules depending on us
_clueBestKnownType[clue] = newType;
foreach (var depender in _cluesDependingOn[clue])
{
_cluesToUpdate.Add(depender);
}
}
}
}
public IEnumerable <string> Errors(ClueId c)
{
return(from e in _clueErrors[c] select e.Message); // TODO: Include source
}
public free <type> Type(ClueId cval)
{
return(_clueBestKnownType[cval]);
}