public RuleSelector(IObservable <dynamic> parsers, IObservable <Grammar> grammars)
{
var entrypoints = parsers
.Zip(grammars, (parser, grammar) => new { parser, grammar })
.Select(p =>
{
var list = new List <ParserEntrypoint>();
if (p.grammar != null)
{
var rules = PublicRuleFinder.Find(p.grammar);
if (rules.StartRule != null)
{
list.Add(new StartRuleEntrypoint(p.parser, rules.StartRule));
}
list.AddRange(rules.PublicRules.Select(rule => new PublicRuleEntrypoint(p.parser, rule)));
list.AddRange(rules.ExportedRules.Select(rule => new ExportedRuleEntrypoint(p.parser, rule)));
}
return(list);
});
this.SelectedEntrypoints = this.WhenAny(x => x.SelectedEntrypoint, selectedEntrypoint => selectedEntrypoint.GetValue());
var intentDetector = Observable.CombineLatest(
entrypoints,
this.SelectedEntrypoints.StartWith(default(ParserEntrypoint)),
this.SelectedEntrypoints.Where(e => e != null).StartWith(default(ParserEntrypoint)),
(list, current, intent) => new { list, current, intent });
this.disposable = new CompositeDisposable(
entrypoints.BindTo(this, x => x.Entrypoints),
intentDetector.Subscribe(tuple =>
{
if (tuple.current == null && tuple.list.Count > 0)
{
ParserEntrypoint intended = null;
if (tuple.intent != null)
{
intended = tuple.list.Where(e => ParserEntrypointEqualityComparer.Instance.Equals(e, tuple.intent)).FirstOrDefault();
}
intended = intended ?? tuple.list.FirstOrDefault();
if (intended != null)
{
this.SelectedEntrypoint = intended;
}
}
}));
}
public ExportedRuleEntrypoint(object parser, Rule rule)
: base("Exported." + PublicRuleFinder.GetPublicName(rule), rule)
{
this.parser = parser;
}
public PublicRuleEntrypoint(object parser, Rule rule)
: base("Parse" + PublicRuleFinder.GetPublicName(rule), rule)
{
this.parser = parser;
this.methodInfo = parser?.GetType().GetMethod(this.Name);
}
