diff --git a/Trs80.Level1Basic.Extensions/Extensions/StringExtensions.cs b/Trs80.Level1Basic.Extensions/Extensions/StringExtensions.cs
index aab86ca..2410036 100644
--- a/Trs80.Level1Basic.Extensions/Extensions/StringExtensions.cs
+++ b/Trs80.Level1Basic.Extensions/Extensions/StringExtensions.cs
@@ -1,8 +1,6 @@
 using System;
-using System.Collections.Generic;
 using System.Diagnostics.CodeAnalysis;
 using System.Linq;
-using System.Text;
 
 namespace Trs80.Level1Basic.Common.Extensions;
 
@@ -11,83 +9,21 @@ public static class StringExtensions
 {
     public static string ToPascalCase(this string text)
     {
-        string result = HandleBaseCases(text, true);
-        if (!string.IsNullOrEmpty(result)) return result;
+        if (string.IsNullOrEmpty(text)) return text;
+        if (text.Length == 1) return text.ToUpper();
 
-        string[] words = SplitWords(text);
+        string[] words = text.Split(new[] { '-', '_' }, StringSplitOptions.RemoveEmptyEntries);
 
         if (words.Length > 1)
             return string.Concat(words.Select(word => word[..1].ToUpper() + word[1..].ToLower()));
 
-        return words[0][..1].ToUpper() + words[0][1..].ToLower();
-    }
-
-    private static string[] SplitWords(string text)
-    {
-        string[] words = text.Split(new[] { '-', '_', ' ' }, StringSplitOptions.RemoveEmptyEntries);
-        return words;
+        return words[0][..1].ToUpper() + words[0][1..];
     }
 
     public static string ToCamelCase(this string text)
     {
-        string result = HandleBaseCases(text, false);
-        if (!string.IsNullOrEmpty(result)) return result;
-
-        result = ToPascalCase(text);
+        string result = ToPascalCase(text);
 
         return result[..1].ToLower() + result[1..];
     }
-
-    public static string ToSnakeCase(this string text)
-    {
-        string result = HandleBaseCases(text, false);
-        if (!string.IsNullOrEmpty(result)) return result;
-
-        string[] words = SplitWords(text);
-
-        return CasedStringWithSeparator(words, false, '_');
-    }
-
-    public static string ToCapsCase(this string text)
-    {
-        string result = HandleBaseCases(text, true);
-        if (!string.IsNullOrEmpty(result)) return result;
-
-        string[] words = SplitWords(text);
-
-        return CasedStringWithSeparator(words, true, '_');
-    }
-
-    public static string ToKebabCase(this string text)
-    {
-        string result = HandleBaseCases(text, false);
-        if (!string.IsNullOrEmpty(result)) return result;
-
-        string[] words = SplitWords(text);
-
-        return CasedStringWithSeparator(words, false, '-');
-    }
-
-    private static string HandleBaseCases(this string text, bool isUpper)
-    {
-        if (string.IsNullOrEmpty(text)) return text;
-        return text.Length == 1 ? text.ConvertCase(isUpper) : string.Empty;
-    }
-    private static string ConvertCase(this string word, bool isUpper)
-    {
-        return isUpper ? word.ToUpper() : word.ToLower();
-    }
-
-    private static string CasedStringWithSeparator(IReadOnlyList<string> words, bool isUpper, char separator)
-    {
-        if (words.Count == 1) return words[0].ConvertCase(isUpper);
-
-        StringBuilder sb = new();
-        
-        for (int i = 0; i < words.Count - 1; i++)
-            sb.Append(words[i].ConvertCase(isUpper) + separator);
-
-        sb.Append(words[^1].ConvertCase(isUpper));
-        return sb.ToString();
-    }
 }
\ No newline at end of file
diff --git a/Trs80.Level1Basic.VirtualMachine/Interpreter/IInterpreter.cs b/Trs80.Level1Basic.VirtualMachine/Interpreter/IInterpreter.cs
index 3375cde..06e63f0 100644
--- a/Trs80.Level1Basic.VirtualMachine/Interpreter/IInterpreter.cs
+++ b/Trs80.Level1Basic.VirtualMachine/Interpreter/IInterpreter.cs
@@ -4,7 +4,7 @@
 
 namespace Trs80.Level1Basic.VirtualMachine.Interpreter;
 
-public interface IInterpreter : IExpressionVisitor, IStatementVisitor
+public interface IInterpreter : IExpressionVisitor<object>, IStatementVisitor<object>
 {
     Statement CurrentStatement { get; }
     void Interpret(ParsedLine line);
diff --git a/Trs80.Level1Basic.VirtualMachine/Interpreter/Interpreter.cs b/Trs80.Level1Basic.VirtualMachine/Interpreter/Interpreter.cs
index 8114dca..dde11fd 100644
--- a/Trs80.Level1Basic.VirtualMachine/Interpreter/Interpreter.cs
+++ b/Trs80.Level1Basic.VirtualMachine/Interpreter/Interpreter.cs
@@ -226,7 +226,7 @@ private void WriteFloatValue(dynamic value)
             _sb.Append(value.ToString("######"));
     }
 
-    public void VisitNextStatement(Next statement)
+    public sd VisitNextStatement(Next statement)
     {
         ForCheckCondition checkCondition = GetCheckCondition(statement);
         dynamic nextIndexerValue = IncrementIndexer(checkCondition);
diff --git a/Trs80.Level1Basic.sln b/Trs80.Level1Basic.sln
index 59a5946..4cec591 100644
--- a/Trs80.Level1Basic.sln
+++ b/Trs80.Level1Basic.sln
@@ -48,8 +48,6 @@ Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Trs80.Level1Basic.TestUtili
 EndProject
 Project("{9A19103F-16F7-4668-BE54-9A1E7A4F7556}") = "Trs80.Level1Basic.VirtualMachine", "Trs80.Level1Basic.VirtualMachine\Trs80.Level1Basic.VirtualMachine.csproj", "{827C9838-033A-4044-B091-E0C6FE509DDC}"
 EndProject
-Project("{FAE04EC0-301F-11D3-BF4B-00C04F79EFBC}") = "Trs80.Level1Basic.Extensions.Test", "Trs80.Level1Basic.Extensions.Test\Trs80.Level1Basic.Extensions.Test.csproj", "{464C903C-6EE4-4629-9031-5D877E0B96E6}"
-EndProject
 Global
 	GlobalSection(SolutionConfigurationPlatforms) = preSolution
 		Debug|Any CPU = Debug|Any CPU
@@ -104,10 +102,6 @@ Global
 		{827C9838-033A-4044-B091-E0C6FE509DDC}.Debug|Any CPU.Build.0 = Debug|Any CPU
 		{827C9838-033A-4044-B091-E0C6FE509DDC}.Release|Any CPU.ActiveCfg = Release|Any CPU
 		{827C9838-033A-4044-B091-E0C6FE509DDC}.Release|Any CPU.Build.0 = Release|Any CPU
-		{464C903C-6EE4-4629-9031-5D877E0B96E6}.Debug|Any CPU.ActiveCfg = Debug|Any CPU
-		{464C903C-6EE4-4629-9031-5D877E0B96E6}.Debug|Any CPU.Build.0 = Debug|Any CPU
-		{464C903C-6EE4-4629-9031-5D877E0B96E6}.Release|Any CPU.ActiveCfg = Release|Any CPU
-		{464C903C-6EE4-4629-9031-5D877E0B96E6}.Release|Any CPU.Build.0 = Release|Any CPU
 	EndGlobalSection
 	GlobalSection(SolutionProperties) = preSolution
 		HideSolutionNode = FALSE
@@ -126,7 +120,6 @@ Global
 		{CCDDE474-9B7C-4300-9962-9C56996F91B0} = {CD571827-E0DE-4EEA-BCCE-3475124C8BB2}
 		{C0766798-3B89-476D-A53B-2B18ACA2529E} = {CD571827-E0DE-4EEA-BCCE-3475124C8BB2}
 		{827C9838-033A-4044-B091-E0C6FE509DDC} = {EC14AF9B-5F4B-4EFC-AE2F-0F5EF3AD0F55}
-		{464C903C-6EE4-4629-9031-5D877E0B96E6} = {CD571827-E0DE-4EEA-BCCE-3475124C8BB2}
 	EndGlobalSection
 	GlobalSection(ExtensibilityGlobals) = postSolution
 		SolutionGuid = {5EB0E852-7B78-46A4-934D-25D7E53322B7}