public void TestTrueGenericsAmbiguity()
{
var name = new NonTerminal("Name");
var argList = new NonTerminal("List<Exp>");
var genericParameters = new NonTerminal("Gen");
var optionalGenericParameters = new NonTerminal("Opt<Gen>");
var cmp = new NonTerminal("Cmp");
var rules = new[]
{
new Rule(Start, Exp),
new Rule(Exp, ID),
new Rule(Exp, OPEN_PAREN, Exp, CLOSE_PAREN),
new Rule(Exp, ID, cmp, Exp),
new Rule(Exp, name, OPEN_PAREN, argList, CLOSE_PAREN),
new Rule(cmp, LT),
new Rule(cmp, GT),
new Rule(argList, Exp),
new Rule(argList, Exp, COMMA, argList),
new Rule(name, ID, optionalGenericParameters),
new Rule(optionalGenericParameters),
new Rule(optionalGenericParameters, genericParameters),
new Rule(genericParameters, LT, ID, GT)
};
// currently this fails due to duplicate prefixes
var ex = Assert.Throws <NotSupportedException>(() => ParserBuilder.CreateParser(rules));
this.output.WriteLine(ex.Message);
var nodes = ParserBuilder.CreateParser(
rules,
new Dictionary <IReadOnlyList <Symbol>, Rule>
{
{
// note: this is more minimal than ideal; id<id>() is not ambiguous
new[] { ID, LT, ID, GT, OPEN_PAREN, ID },
rules.Single(r => r.Symbols.SequenceEqual(new Symbol[] { name, OPEN_PAREN, argList, CLOSE_PAREN }))
},
}
);
var parser = new ParserNodeParser(nodes, Start, this.output.WriteLine);
var listener = new TreeListener();
// compares: id < id > (id) vs. call: id<id>(id) => our resolution says call
parser.Parse(new[] { ID, LT, ID, GT, OPEN_PAREN, ID, CLOSE_PAREN }, listener);
this.output.WriteLine(listener.Root.Flatten().ToString());
listener.Root.Flatten().ToString().ShouldEqual("Start(Exp(Name(ID, Opt<Gen>(Gen(<, ID, >))), (, List<Exp>(Exp(ID)), )))");
}
public void TestGenericsAmbiguity()
{
var name = new NonTerminal("Name");
var nameListOption = new NonTerminal("Opt<List<Name>>");
var nameList = new NonTerminal("List<Name>");
var genericParameters = new NonTerminal("Gen");
var optionalGenericParameters = new NonTerminal("Opt<Gen>");
var rules = new[]
{
new Rule(Exp, name),
new Rule(name, ID, optionalGenericParameters),
new Rule(optionalGenericParameters),
new Rule(optionalGenericParameters, genericParameters),
new Rule(genericParameters, LT, nameListOption, GT),
new Rule(nameListOption),
new Rule(nameListOption, nameList),
new Rule(nameList, name),
new Rule(nameList, name, COMMA, nameList)
};
var nodes1 = ParserBuilder.CreateParser(rules);
var parser1 = new ParserNodeParser(nodes1, Exp, this.output.WriteLine);
var listener1 = new TreeListener();
parser1.Parse(new[] { ID, LT, ID, COMMA, ID, GT }, listener1);
this.output.WriteLine(listener1.Root.Flatten().ToString());
listener1.Root.Flatten().ToString().ShouldEqual("Exp(Name(ID, Opt<Gen>(Gen(<, Opt<List<Name>>(List<Name>(Name(ID, Opt<Gen>()), ,, Name(ID, Opt<Gen>()))), >))))");
var cmp = new NonTerminal("Cmp");
var ambiguousRules = rules.Concat(new[]
{
new Rule(cmp, LT),
new Rule(cmp, GT),
new Rule(Exp, ID, cmp, Exp),
})
.ToArray();
this.output.WriteLine("*********** MORE AMBIGUOUS CASE ***********");
var nodes2 = ParserBuilder.CreateParser(ambiguousRules);
var parser2 = new ParserNodeParser(nodes2, Exp, this.output.WriteLine);
var listener2 = new TreeListener();
// id < id<id<id>>
parser2.Parse(new[] { ID, LT, ID, LT, ID, LT, ID, GT, GT }, listener2);
this.output.WriteLine(listener2.Root.Flatten().ToString());
listener2.Root.Flatten()
.ToString()
.ShouldEqual("Exp(ID, Cmp(<), Exp(Name(ID, Opt<Gen>(Gen(<, Opt<List<Name>>(List<Name>(Name(ID, Opt<Gen>(Gen(<, Opt<List<Name>>(List<Name>(Name(ID, Opt<Gen>()))), >))))), >)))))");
}
public void TestCastAmbiguity()
{
var cast = new NonTerminal("Cast");
var term = new NonTerminal("Term");
var minus = new Token("-");
var rules = new[]
{
new Rule(Start, Exp),
new Rule(Exp, term),
new Rule(Exp, term, minus, Exp),
new Rule(term, ID),
new Rule(term, OPEN_PAREN, Exp, CLOSE_PAREN),
new Rule(term, cast),
new Rule(cast, OPEN_PAREN, ID, CLOSE_PAREN, Exp),
};
var ex = Assert.Throws <NotSupportedException>(() => ParserBuilder.CreateParser(rules));
this.output.WriteLine(ex.Message);
var nodes = ParserBuilder.CreateParser(
rules,
new Dictionary <IReadOnlyList <Symbol>, Rule>
{
{
new[] { term },
rules.Single(r => r.Symbols.SequenceEqual(new Symbol[] { term, minus, Exp }))
},
}
);
var parser = new ParserNodeParser(nodes, Start, this.output.WriteLine);
var listener = new TreeListener();
// (id)((id) - id)
parser.Parse(new[] { OPEN_PAREN, ID, CLOSE_PAREN, OPEN_PAREN, OPEN_PAREN, ID, CLOSE_PAREN, minus, ID, CLOSE_PAREN }, listener);
this.output.WriteLine(listener.Root.Flatten().ToString());
listener.Root.Flatten().ToString()
.ShouldEqual("Start(Exp(Term(Cast((, ID, ), Exp(Term((, Exp(Term((, Exp(Term(ID)), )), -, Exp(Term(ID))), )))))))");
}
public void TestExpressionVsStatementListConflict()
{
var rules = new[]
{
new Rule(Start, Stmt),
new Rule(Stmt, Exp, SEMICOLON),
new Rule(Exp, ID),
new Rule(Exp, OPEN_BRACKET, ExpList, CLOSE_BRACKET),
new Rule(Exp, OPEN_BRACKET, Stmt, StmtList, CLOSE_BRACKET),
new Rule(ExpList),
new Rule(ExpList, Exp, ExpList),
new Rule(StmtList),
new Rule(StmtList, Stmt, StmtList)
};
var nodes = ParserBuilder.CreateParser(rules);
//var parser = new ParserGenerator(rules).Create();
var parser1 = new ParserNodeParser(nodes, Start);
var listener1 = new TreeListener();
// [];
parser1.Parse(new[] { OPEN_BRACKET, CLOSE_BRACKET, SEMICOLON }, listener1);
this.output.WriteLine(listener1.Root.Flatten().ToString());
listener1.Root.Flatten().ToString().ShouldEqual("Start(Stmt(Exp([, List<Exp>(), ]), ;))");
this.output.WriteLine(Environment.NewLine + "///////////////// CASE 2 /////////////////" + Environment.NewLine);
var parser2 = new ParserNodeParser(nodes, Start, this.output.WriteLine);
var listener2 = new TreeListener();
// [ [ id; ] [ [] id ] ];
parser2.Parse(new[] { OPEN_BRACKET, OPEN_BRACKET, ID, SEMICOLON, CLOSE_BRACKET, OPEN_BRACKET, OPEN_BRACKET, CLOSE_BRACKET, ID, CLOSE_BRACKET, CLOSE_BRACKET, SEMICOLON }, listener2);
this.output.WriteLine(listener2.Root.Flatten().ToString());
listener2.Root.Flatten().ToString().ShouldEqual("Start(Stmt(Exp([, List<Exp>(Exp([, Stmt(Exp(ID), ;), List<Stmt>(), ]), Exp([, List<Exp>(Exp([, List<Exp>(), ]), Exp(ID)), ])), ]), ;))");
}
public void TestLL1()
{
var rules = new[]
{
new Rule(Start, StmtList),
new Rule(StmtList),
new Rule(StmtList, Stmt, StmtList),
new Rule(Stmt, Exp, SEMICOLON),
new Rule(Exp, ID),
new Rule(Exp, OPEN_BRACKET, ExpList, CLOSE_BRACKET),
new Rule(ExpList),
new Rule(ExpList, Exp, ExpList)
};
var nodes = ParserBuilder.CreateParser(rules);
var parser = new ParserNodeParser(nodes, Start, this.output.WriteLine);
var listener = new TreeListener();
parser.Parse(new[] { ID, SEMICOLON, OPEN_BRACKET, ID, OPEN_BRACKET, ID, ID, CLOSE_BRACKET, CLOSE_BRACKET, SEMICOLON }, listener);
this.output.WriteLine(listener.Root.Flatten().ToString());
listener.Root.Flatten().ToString()
.ShouldEqual("Start(List<Stmt>(Stmt(Exp(ID), ;), Stmt(Exp([, List<Exp>(Exp(ID), Exp([, List<Exp>(Exp(ID), Exp(ID)), ])), ]), ;)))");
}
