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;
}
}
}));
}
private static ParseResult ParseTest(ParserEntrypoint entrypoint, string subject)
{
if (entrypoint == null)
{
return(new ParseResult
{
Errors = new CompilerError[0],
Result = null,
});
}
subject = subject ?? string.Empty;
try
{
var tracer = new WarningsPerformanceTracer();
var result = entrypoint.Parse(subject, SentinelFileName, tracer);
return(new ParseResult
{
Result = result,
Errors = tracer.Recommendations,
});
}
catch (Exception ex)
{
var cursor = ex.Data["cursor"] as Cursor ?? new Cursor(subject, 0, SentinelFileName);
var parts = Regex.Split(ex.Message, @"(?<=^\w+):");
if (parts.Length == 1)
{
parts = new[] { string.Empty, parts[0] };
}
return(new ParseResult
{
Errors = new List <CompilerError>
{
new CompilerError(SentinelFileName, cursor.Line, cursor.Column, errorNumber: parts[0], errorText: parts[1]),
}.AsReadOnly(),
});
}
}