Work on type checking variables when getting them from tables

Upsilon/Binder/Binder.cs

@@ -254,7 +254,7 @@ namespace Upsilon.Binder
                 {
                     var tableExpression = (BoundTableExpression) assignment;
                     variable = new TableVariableSymbol(name, tableExpression.ValueType, isLocal,
-                        tableExpression.Expressions.Values.ToArray());
+                        tableExpression.Expressions);
                 }
                 else
                 {
@@ -472,7 +472,6 @@ namespace Upsilon.Binder
         {
             var keyType = Type.Unknown;
             var valueType = Type.Unknown;
-            var dictionary = new Dictionary<string, bool>();
             var statements = ImmutableArray.CreateBuilder<BoundStatement>();
             var s = Scope;
             Scope = BoundScope.WithReadOnlyScope(s);
@@ -500,6 +499,14 @@ namespace Upsilon.Binder
             switch (expression.Type)
             {
                 case Type.Table:
+                    if (expression.Kind == BoundKind.BoundTableExpression && index.Kind == BoundKind.BoundLiteralExpression)
+                    {
+                        var table = (BoundTableExpression)expression;
+                        var realIndex = (BoundLiteralExpression) index;
+                        var variable = table.Expressions[realIndex.Value.ToString()];
+                        return new BoundIndexExpression(expression, index, variable.Type, e.Span);
+                    }
+                    return new BoundIndexExpression(expression, index, Type.Unknown, e.Span);
                 case Type.UserData:
                 case Type.Unknown:
                     return new BoundIndexExpression(expression, index, Type.Unknown, e.Span);
@@ -518,11 +525,34 @@ namespace Upsilon.Binder
             switch (expression.Type)
             {
                 case Type.Table:
+                    if (expression.Kind == BoundKind.BoundTableExpression)
+                    {
+                        var table     = (BoundTableExpression)expression;
+                        if (table.Expressions.TryGetValue(index, out var variable))
+                        {
+                            return new BoundFullStopIndexExpression(expression, index, variable.Type, e.Span);
+                        }
+                        _diagnostics.LogError($"No variable {index} found in table.", e.Span);
+                    }
+                    if (expression.Kind == BoundKind.VariableExpression)
+                    {
+                        var table    = (BoundVariableExpression)expression;
+                        var realTable = table.Variable;
+                        var variableDic = ((TableVariableSymbol) realTable.VariableSymbol).Variables;
+                        if (variableDic.TryGetValue(index, out var variable))
+                        {
+                            return new BoundFullStopIndexExpression(expression, index, variable.Type, e.Span);
+                        }
+
+                        _diagnostics.LogError($"No variable {index} found in table {realTable.VariableSymbol.Name}.",
+                            e.Span);
+                    }
+                    return new BoundFullStopIndexExpression(expression, index, Type.Unknown, e.Span);
                 case Type.UserData:
                 case Type.Unknown:
-                    return new BoundFullStopIndexExpression(expression, index, e.Span);
+                    return new BoundFullStopIndexExpression(expression, index, Type.Unknown, e.Span);
                 case Type.String:
-                    return new BoundFullStopIndexExpression(expression, index, e.Span);
+                    return new BoundFullStopIndexExpression(expression, index, Type.String, e.Span);
                 default:
                     _diagnostics.LogInvalidIndexExpression(expression.Type, Type.String, e.Span);
                     return new BoundLiteralExpression(new ScriptNull(), e.Span);

Upsilon/Binder/BoundExpressions/BoundIndexExpression.cs

@@ -35,10 +35,11 @@ namespace Upsilon.Binder
         public BoundExpression Expression { get; }
         public string Index { get; }
 
-        public BoundFullStopIndexExpression(BoundExpression expression, string index, TextSpan span) : base(span)
+        public BoundFullStopIndexExpression(BoundExpression expression, string index, Type type, TextSpan span) : base(span)
         {
             Expression = expression;
             Index = index;
+            Type = type;
         }
 
         public override BoundKind Kind => BoundKind.BoundFullstopIndexExpression;
@@ -49,6 +50,6 @@ namespace Upsilon.Binder
             return this;
         }
 
-        public override Type Type => Type.Unknown;
+        public override Type Type { get; }
     }
 }

Upsilon/Binder/VariableSymbol.cs

@@ -1,3 +1,4 @@
+using System.Collections.Generic;
 using System.Collections.Immutable;
 using Upsilon.BaseTypes;
 
@@ -34,9 +35,9 @@ namespace Upsilon.Binder
     public class TableVariableSymbol : VariableSymbol
     {
         public Type OutType { get; }
-        public VariableSymbol[] Variables { get; }
+        public Dictionary<string, VariableSymbol> Variables { get; }
 
-        public TableVariableSymbol(string name, Type outType, bool local, VariableSymbol[] variables)
+        public TableVariableSymbol(string name, Type outType, bool local, Dictionary<string, VariableSymbol> variables)
         :base (name, Type.Table, local)
         {
             OutType = outType;