static void Main(string[] arguments)
{
#region Classic Space Object Collision Example
/*
* See https://en.wikipedia.org/wiki/Multiple_dispatch#Examples
*/
var planet1 = new Planet();
var planet2 = new Planet();
var asteroid1 = new Asteroid();
var asteroid2 = new Asteroid();
var spaceship1 = new Spaceship();
var spaceship2 = new Spaceship();
var satellite1 = new TelecomSatellite();
var satellite2 = new TelecomSatellite();
System.Diagnostics.Debug.Assert(planet1.CollideWith(planet2) == "the planets destroy each other");
System.Diagnostics.Debug.Assert(planet1.CollideWith(asteroid1) == "the planet obliterates the asteroid");
System.Diagnostics.Debug.Assert(asteroid1.CollideWith(planet1) == "the planet obliterates the asteroid");
System.Diagnostics.Debug.Assert(planet1.CollideWith(spaceship1) == "the planet obliterates the spaceship");
System.Diagnostics.Debug.Assert(spaceship1.CollideWith(planet1) == "the planet obliterates the spaceship");
System.Diagnostics.Debug.Assert(planet1.CollideWith(satellite1) == "the planet obliterates the satellite");
System.Diagnostics.Debug.Assert(satellite1.CollideWith(planet1) == "the planet obliterates the satellite");
System.Diagnostics.Debug.Assert(asteroid1.CollideWith(asteroid2) == "the asteroids destroy each other");
System.Diagnostics.Debug.Assert(asteroid1.CollideWith(spaceship1) == "the asteroid obliterates the spaceship");
System.Diagnostics.Debug.Assert(spaceship1.CollideWith(asteroid1) == "the asteroid obliterates the spaceship");
System.Diagnostics.Debug.Assert(asteroid1.CollideWith(satellite1) == "the asteroid obliterates the satellite");
System.Diagnostics.Debug.Assert(satellite1.CollideWith(asteroid1) == "the asteroid obliterates the satellite");
System.Diagnostics.Debug.Assert(spaceship1.CollideWith(spaceship2) == "the spaceships destroy each other");
System.Diagnostics.Debug.Assert(spaceship1.CollideWith(satellite1) == "the spaceship obliterates the satellite");
System.Diagnostics.Debug.Assert(satellite1.CollideWith(spaceship1) == "the spaceship obliterates the satellite");
System.Diagnostics.Debug.Assert(satellite1.CollideWith(satellite2) == "the satellites destroy each other");
#endregion
var testLexicon =
new Lexicon
(
new[]
{
new TokenType("identifier", "[A-Za-z_][A-Za-z_0-9]*", token => token.Match != "null" ? token.Match : null),
new TokenType("text", "\"[^\"]*\"", token => token.Match),
new TokenType("number", "[0-9]+", token => int.Parse(token.Match))
}
);
// Anonymous goodness...
var AnonymousModel = new { Content = default(object) };
var AnonymousReducer = Reducer(default(object), AnonymousModel);
var toAnonymousModel =
NewReducer
(
AnonymousReducer,
(context, outer, expression, value) =>
expression ?? new { Content = value }
);
var aParser = SExpressionParser.Create(testLexicon, AnonymousReducer);
var aModel = aParser.Parse(" ( a 123 ( \"foo\" bar ( ) c ) ( null ) ) ", toAnonymousModel);
System.Diagnostics.Debug.Assert(Is(AnonymousModel, aModel));
System.Diagnostics.Debug.Assert(Is(ListOf(AnonymousModel), As(AnonymousModel, aModel).Content));
System.Diagnostics.Debug.Assert(As(ListOf(AnonymousModel), As(AnonymousModel, aModel).Content)[0].Content is string);
System.Diagnostics.Debug.Assert(As(ListOf(AnonymousModel), As(AnonymousModel, aModel).Content)[0].Content as string == "a");
System.Diagnostics.Debug.Assert(As(ListOf(AnonymousModel), As(AnonymousModel, aModel).Content)[1].Content is int);
System.Diagnostics.Debug.Assert((int)As(ListOf(AnonymousModel), As(AnonymousModel, aModel).Content)[1].Content == 123);
Console.WriteLine();
Console.Write("Press a key>");
Console.ReadKey();
// via extension method : SExpressionBuilder SExpressionBuilder(this object anchor)
var S = default(object).SExpressionBuilder(); // loosely typed use cases (ie, object / object[] S-Exprs)
// via extension method : SExpressionBuilder<TExpression> SExpressionBuilder<TExpression>(this TExpression anchor)
var P = default(PicoNode).SExpressionBuilder(); // strongly typed use cases (ie, PicoNode S-Exprs)
// equiv S-Expr: ( 123 abc ( x y null z ( null ) ) 456 ( ) )
// fluently built
var test1 = S(123, "abc", S("x", "y", null, "z", S(null)), 456, S());
System.Diagnostics.Debug.Assert(test1 is object[]);
System.Diagnostics.Debug.Assert((int)(test1 as object[])[0] == 123); // ( 123 <-
System.Diagnostics.Debug.Assert((string)(test1 as object[])[1] == "abc"); // ( ... abc <-
System.Diagnostics.Debug.Assert((string)((test1 as object[])[2] as object[])[1] == "y"); // ( ... ( ... y <-
System.Diagnostics.Debug.Assert((int)(test1 as object[])[3] == 456); // ( ... ( ... ) 456 <-
System.Diagnostics.Debug.Assert(((object[])(test1 as object[])[4]).Length == 0); // ( ... ( ... ) ... ( ) <-
// equiv S-Expr: ( ( html ) ( ( body ) ( ( p ) "Hello, world!" ( ( br ) ) "Ciao!" ) ) )
// fluently built
var test2 =
P(
P("html"),
P(
P("body"),
P
(
P("p"),
"\"Hello, world!\"",
P(P("br")),
"\"Ciao!\""
)
)
);
System.Diagnostics.Debug.Assert(test2 is PicoNode);
System.Diagnostics.Debug.Assert(test2.IsAtom == false);
System.Diagnostics.Debug.Assert(test2 is IReadOnlyList <PicoNode>);
System.Diagnostics.Debug.Assert(test2[0].IsAtom == false);
System.Diagnostics.Debug.Assert(test2[0][0].IsAtom == true);
System.Diagnostics.Debug.Assert(test2[0][0].Value == "html");
System.Diagnostics.Debug.Assert(test2[1][1][1].IsAtom == true);
System.Diagnostics.Debug.Assert(test2[1][1][1].Value == "\"Hello, world!\"");
System.Diagnostics.Debug.Assert
(
test2.ToString()
==
"( ( System.String{html} ) ( ( System.String{body} ) ( ( System.String{p} ) System.String{\"Hello, world!\"} ( ( System.String{br} ) ) System.String{\"Ciao!\"} ) ) )"
);
Console.WriteLine();
Console.WriteLine($"{nameof(test2)}: {test2}");
// Now for some parsing...
var parse1 =
new SExpressionParser(testLexicon)
.Parse(" ( 123 abc ( x y null z ( null ) ) 456 ( ) ) ");
System.Diagnostics.Debug.Assert(parse1 is SExpression);
System.Diagnostics.Debug.Assert((int)parse1[0].Value == 123); // ( 123 <-
System.Diagnostics.Debug.Assert((string)parse1[1].Value == "abc"); // ( ... abc <-
System.Diagnostics.Debug.Assert((string)parse1[2][1].Value == "y"); // ( ... ( ... y <-
System.Diagnostics.Debug.Assert((string)parse1[2][2].Value == null); // ( ... ( ... null <-
System.Diagnostics.Debug.Assert((int)parse1[3].Value == 456); // ( ... ( ... ) 456 <-
System.Diagnostics.Debug.Assert(parse1[4].Count == 0); // ( ... ( ... ) ... ( ) <-
System.Diagnostics.Debug.Assert
(
parse1.ToString()
==
"( System.Int32{123} System.String{abc} ( System.String{x} System.String{y} System.Object{null} System.String{z} ( System.Object{null} ) ) System.Int32{456} ( ) )"
);
Console.WriteLine();
Console.WriteLine($"{nameof(parse1)}: {parse1}");
var parse2 =
new SExpressionParser <PicoNode>(testLexicon)
.Parse(" ( ( html ) ( ( body ) ( ( p ) \"Hello, world!\" ( ( br ) ) \"Ciao!\" ) ) ) ");
System.Diagnostics.Debug.Assert(parse2 is PicoNode); // Duh.
System.Diagnostics.Debug.Assert(parse2.IsAtom == false);
System.Diagnostics.Debug.Assert(parse2 is IReadOnlyList <PicoNode>);
System.Diagnostics.Debug.Assert(parse2[0].IsAtom == false);
System.Diagnostics.Debug.Assert(parse2[0][0].IsAtom == true);
System.Diagnostics.Debug.Assert(parse2[0][0].Value == "html");
System.Diagnostics.Debug.Assert(parse2[1][1][1].IsAtom == true);
System.Diagnostics.Debug.Assert(parse2[1][1][1].Value == "\"Hello, world!\"");
System.Diagnostics.Debug.Assert(parse2.ToString() == test2.ToString()); // Yup.
Console.WriteLine();
Console.WriteLine($"{nameof(parse2)}: {parse2}");
// Parse errors reporting...
string error1 = null;
try
{
new SExpressionParser(testLexicon).Parse(@" ( 123
( 456 )
)
garbage");
}
catch (Exception ex)
{
error1 = ex.Message;
}
System.Diagnostics.Debug.Assert(error1.StartsWith("syntax error: end of input expected but found identifier garbage at line 4, column 2"));
string error2 = null;
try
{
new SExpressionParser(testLexicon).Parse(@" ( 123 abc
456 ");
}
catch (Exception ex)
{
error2 = ex.Message;
}
System.Diagnostics.Debug.Assert(error2.StartsWith("syntax error: ) expected but found end of input at line 2, column 6"));
string error3 = null;
try
{
new SExpressionParser(testLexicon).Parse(@" (
abc (
?!? )
) ");
}
catch (Exception ex)
{
error3 = ex.Message;
}
System.Diagnostics.Debug.Assert(error3.StartsWith("syntax error: ) expected but found unexpected ?!? at line 3, column 11"));
// And last but not least...
// via extension method:
// Reducer<TContext, TExpression> SExpressionReducer<TContext, TExpression>(this TExpression anchor, TContext prototype, Reducer<TContext, TExpression> reducer)
var reducer =
default(PicoNode) // expression type
.SExpressionReducer
(
default(object), // optional context (ignored)
(ignored, outer, expression, value) =>
(
expression != null ?
(
!expression.IsAtom &&
(expression.Count > 0) &&
!expression[0].IsAtom && // all this to detect the "(tagName)" in "... ( (tagName) ... ) ..."
expression[0].Count == 1 &&
expression[0][0].IsAtom ?
(
outer == null ?
new PicoDocument(new PicoElement(expression[0][0].Value, expression.Skip(1)))
:
(PicoNode) new PicoElement(expression[0][0].Value, expression.Skip(1))
)
:
(
expression.IsAtom &&
expression.Value.StartsWith("\"") &&
expression.Value.EndsWith("\"") ?
new PicoText(expression.Value)
:
expression
)
)
:
(
value is IEnumerable <PicoNode>?
new PicoNode((IEnumerable <PicoNode>)value)
:
new PicoNode((string)value)
)
)
);
/*
* compare to:
* <html>
* <body>
* <p>
* Hello, world!
* <br/>
* Ciao!
* </p>
* </html>
* ...
*/
var parse3 =
new SExpressionParser <PicoNode>(testLexicon)
.Parse(@"
(
( html )
(
( body )
(
( p ) ""Hello, world!""
( ( br ) )
""Ciao!""
)
)
) ", reducer); // <- note the passing of the reducer
System.Diagnostics.Debug.Assert(parse3 is PicoDocument);
var documentElement = ((PicoDocument)parse3).DocumentElement;
System.Diagnostics.Debug.Assert(documentElement.TagName == "html");
System.Diagnostics.Debug.Assert(documentElement[0] is PicoElement);
System.Diagnostics.Debug.Assert((documentElement[0] as PicoElement).TagName == "body");
System.Diagnostics.Debug.Assert(documentElement[0][0] is PicoElement);
System.Diagnostics.Debug.Assert((documentElement[0][0] as PicoElement).TagName == "p");
System.Diagnostics.Debug.Assert(documentElement[0][0][0] is PicoText);
System.Diagnostics.Debug.Assert((documentElement[0][0][0] as PicoText).Value == "\"Hello, world!\"");
System.Diagnostics.Debug.Assert
(
parse3.ToString()
==
"(<html><body><p>Hello, world!<br/>Ciao!</p></body></html>)"
);
Console.WriteLine();
Console.WriteLine($"{nameof(parse3)}: {parse3}");
//var input = System.IO.File.ReadAllText(TEST_SEXPR_FILE_PATH);
//var parser = new SExpressionParser<PicoNode>();
//Console.WriteLine();
//Console.Write("Press a key>");
//Console.ReadKey();
//var sw = new System.Diagnostics.Stopwatch();
//sw.Start();
//var parse4 = parser.Parse(input, new FastLexer(), reducer);
//sw.Stop();
//Console.WriteLine();
//Console.WriteLine($"{nameof(parse4)}: elapsed: {sw.ElapsedMilliseconds.ToString("0,0")} ms.");
//Console.WriteLine();
//Console.Write("Press a key>");
//Console.ReadKey();
//var body = (PicoElement)((PicoDocument)parse4).DocumentElement[0];
//var firstParagraph = (PicoElement)body[0];
//Console.WriteLine();
//Console.WriteLine($"{nameof(parse4)}: '{body.TagName}' has {body.Count} child nodes '{firstParagraph.TagName}'");
//Console.WriteLine();
//Console.Write("Press a key>");
//Console.ReadKey();
//Console.WriteLine();
//Console.WriteLine($"{nameof(parse4)}: {parse4}");
Console.WriteLine();
Console.Write("The end>");
Console.ReadKey();
}
protected string CollideWith(Spaceship spaceship) => spaceship.CollideWith(this);