work on nested tables, will need some cleanup later

Upsilon/Binder/Binder.cs

@@ -387,24 +387,16 @@ namespace Upsilon.Binder
 
         private BoundExpression BindIndexExpression(IndexExpressionSyntax e)
         {
-            var name = e.Identifier.Name;
+            var expression = BindExpression(e.Expression);
-            if (!Scope.TryGetVariable(name, true, out var variable))
+            if (expression.Type != Type.Table && expression.Type != Type.Unknown)
             {
-                _diagnostics.LogUnknownVariable(e.Identifier.Span, name);
+                //TODO: wrong type diagnostic
+                throw new Exception(expression.Type.ToString());
                 return new BoundLiteralExpression(new LuaNull());
             }
 
-            if (variable.Type != Type.Table)
-            {
-                //TODO better error message
-                _diagnostics.LogUnknownVariable(e.Identifier.Span, name);
-                return new BoundLiteralExpression(new LuaNull());
-            }
-
-            var tableVariable = (TableVariableSymbol) variable;
-            var outType = tableVariable.OutType;
             var index = BindExpression(e.Index);
-            return new BoundIndexExpression(tableVariable, index, outType);
+            return new BoundIndexExpression(expression, index, Type.Unknown);
         }
     }
 }

Upsilon/Binder/BoundExpressions/BoundIndexExpression.cs

@@ -5,14 +5,14 @@ namespace Upsilon.Binder
 {
     public class BoundIndexExpression : BoundExpression
     {
-        public BoundIndexExpression(TableVariableSymbol identifier, BoundExpression index, Type type)
+        public BoundIndexExpression(BoundExpression identifier, BoundExpression index, Type type)
         {
             Identifier = identifier;
             Index = index;
             Type = type;
         }
 
-        public TableVariableSymbol Identifier { get; }
+        public BoundExpression Identifier { get; }
         public BoundExpression Index { get; }
 
         public override BoundKind Kind => BoundKind.BoundIndexExpression;

Upsilon/Evaluator/Evaluator.cs

@@ -333,20 +333,36 @@ namespace Upsilon.Evaluator
 
         private LuaType EvaluateIndexExpression(BoundIndexExpression e)
         {
-            if (!Scope.TryGet(e.Identifier, out var val))
+            IIndexable index;
+            if (e.Identifier.Kind == BoundKind.VariableExpression)
             {
-                throw new Exception($"Cannot find variable: '{e.Identifier.Name}'");
+                var variableExpression = (BoundVariableExpression) e.Identifier;
+                var variable = variableExpression.Variable;
+                if (!Scope.TryGet(variable, out var val))
+                {
+                    throw new Exception($"Cannot find variable: '{variable.Name}'");
+                }
+
+                if (!(val is IIndexable indexable))
+                {
+                    throw new Exception("Variable is not indexable.");
+                }
+                index = indexable;
+            }
+            else if (e.Identifier.Kind == BoundKind.BoundIndexExpression)
+            {
+                var indexExpression = (BoundIndexExpression)e.Identifier;
+                index = (IIndexable) EvaluateIndexExpression(indexExpression);
+            }
+            else
+            {
+                throw new Exception();
             }
 
-            if (!(val is IIndexable indexable))
-            {
-                throw new Exception("Variable is not indexable.");
-            }
 
-            var innerEvaluator = new Evaluator(_diagnostics, Scope, indexable.EvaluatorIdentifier);
+            var innerEvaluator = new Evaluator(_diagnostics, Scope, index.EvaluatorIdentifier);
-            var indexer = EvaluateExpression(e.Index);
+            var indexer = innerEvaluator.EvaluateExpression(e.Index);
-
+            return index.Get(indexer.ToString(), Identifier);
-            return indexable.Get(indexer.ToString(), Identifier);
         }
     }
 }

Upsilon/Parser/ExpressionSyntax/IndexExpressionSyntax.cs

@@ -4,15 +4,15 @@ namespace Upsilon.Parser
 {
     public class IndexExpressionSyntax : ExpressionSyntax
     {
-        public IdentifierToken Identifier { get; }
+        public ExpressionSyntax Expression { get; }
         public SyntaxToken OpenBracket { get; }
         public ExpressionSyntax Index { get; }
         public SyntaxToken CloseBracket { get; }
 
-        public IndexExpressionSyntax(IdentifierToken identifier, SyntaxToken openBracket, ExpressionSyntax index,
+        public IndexExpressionSyntax(ExpressionSyntax expression, SyntaxToken openBracket, ExpressionSyntax index,
             SyntaxToken closeBracket)
         {
-            Identifier = identifier;
+            Expression = expression;
             OpenBracket = openBracket;
             Index = index;
             CloseBracket = closeBracket;
@@ -21,7 +21,7 @@ namespace Upsilon.Parser
         public override SyntaxKind Kind => SyntaxKind.IndexExpression;
         public override IEnumerable<SyntaxNode> ChildNodes()
         {
-            yield return Identifier;
+            yield return Expression;
             yield return OpenBracket;
             yield return Index;
             yield return CloseBracket;

Upsilon/Parser/IdentifierToken.cs

@@ -4,7 +4,8 @@ namespace Upsilon.Parser
 {
     public class IdentifierToken : SyntaxToken
     {
-        public IdentifierToken(string name, int position, int length) : base(SyntaxKind.Identifier, position, name, null)
+        public IdentifierToken(string name, int position)
+            : base(SyntaxKind.Identifier, position, name, null)
         {
             Name = name;
         }

Upsilon/Parser/Lexer.cs

@@ -166,7 +166,7 @@ namespace Upsilon.Parser
             var str = stringBuilder.ToString();
             if (kind == SyntaxKind.Identifier)
             {
-                return new IdentifierToken(str, start, str.Length);
+                return new IdentifierToken(str, start);
             }
             return new SyntaxToken(kind, start, str, null);
         }

Upsilon/Parser/Parser.cs

@@ -167,7 +167,12 @@ namespace Upsilon.Parser
 
         private ExpressionSyntax ParseExpression()
         {
-            return ParseBinaryExpression();
+            var expression = ParseBinaryExpression();
+            while (Current.Kind == SyntaxKind.OpenBracket)
+            {
+                expression = ParseIndexExpression(expression);
+            }
+            return expression;
         }
 
         private AssignmentExpressionSyntax ParseAssignmentExpression()
@@ -214,34 +219,45 @@ namespace Upsilon.Parser
 
         private ExpressionSyntax ParsePrimaryExpression()
         {
+            ExpressionSyntax expression;
             switch (Current.Kind)
             {
                 case SyntaxKind.OpenParenthesis:
-                    return ParseParenthesizedExpression();
+                    expression = ParseParenthesizedExpression();
+                    break;
                 case SyntaxKind.Number:
-                    return ParseNumber();
+                    expression = ParseNumber();
+                    break;
                 case SyntaxKind.TrueKeyword:
                 case SyntaxKind.FalseKeyword:
-                    return ParseBoolean();
+                    expression = ParseBoolean();
+                    break;
                 case SyntaxKind.String:
-                    return ParseString();
+                    expression = ParseString();
+                    break;
                 case SyntaxKind.Identifier:
                     if (Next.Kind == SyntaxKind.OpenParenthesis)
-                        return ParseFunctionCallExpression();
+                        expression = ParseFunctionCallExpression();
-                    if (Next.Kind == SyntaxKind.OpenBracket)
+                    else
-                        return ParseIndexExpression();
+                    {
-                    var token = MatchToken(SyntaxKind.Identifier);
+                        var token = MatchToken(SyntaxKind.Identifier);
-                    return new VariableExpressionSyntax((IdentifierToken) token);
+                        expression = new VariableExpressionSyntax((IdentifierToken) token);
+                    }
+                    break;
                 case SyntaxKind.OpenBrace:
-                    return ParseTable();
+                    expression = ParseTable();
+                    break;
                 case SyntaxKind.NilKeyword:
                     var nilToken = MatchToken(SyntaxKind.NilKeyword);
-                    return new LiteralExpressionSyntax(nilToken, null);
+                    expression = new LiteralExpressionSyntax(nilToken, null);
+                    break;
                 default:
                     _diagnostics.LogBadCharacter(new TextSpan(_position, 1), SyntaxKind.Identifier);
                     NextToken();
-                    return new BadExpressionSyntax();
+                    expression = new BadExpressionSyntax();
+                    break;
             }
+            return expression;
         }
 
         private ExpressionSyntax ParseFunctionCallExpression()
@@ -262,13 +278,12 @@ namespace Upsilon.Parser
                 parameters.ToImmutable(), closeParenthesis);
         }
 
-        private ExpressionSyntax ParseIndexExpression()
+        private ExpressionSyntax ParseIndexExpression(ExpressionSyntax expression)
         {
-            var identifier = (IdentifierToken)MatchToken(SyntaxKind.Identifier);
             var openBracket = MatchToken(SyntaxKind.OpenBracket);
             var index = ParseExpression();
             var closeBracket = MatchToken(SyntaxKind.CloseBracket);
-            return new IndexExpressionSyntax(identifier, openBracket, index, closeBracket);
+            return new IndexExpressionSyntax(expression, openBracket, index, closeBracket);
         }
 
         private ExpressionSyntax ParseParenthesizedExpression()

UpsilonTests/TableTests.cs

@@ -57,6 +57,27 @@ return table[""test""]
             Assert.Null(evaluated);
         }
 
+        [Fact]
+        public void NestedTables()
+        {
+            const string input = @"
+table = {
+    {
+        {
+            100, 600, 900
+        },
+        {}
+    }
+}
+return table[1][1][2]
+";
+            var script = new Script(input);
+            Assert.Empty(script.Diagnostics.Messages);
+            var evaluated = script.Evaluate<long>();
+            Assert.Empty(script.Diagnostics.Messages);
+            Assert.Equal(600, evaluated);
+        }
+
         [Fact]
         public void FunctionsInTable()
         {

Ycicle/Program.cs

@@ -31,6 +31,7 @@ namespace Ycicle
                     Console.ResetColor();
                     continue;
                 }
+                //Console.WriteLine(script.PrettyPrintSyntaxTree());
 
                 var evaluate = script.Evaluate();
                 if (script.Diagnostics.Messages.Count > 0)