More datahandler stuff, removed SzOperationResult.cs and made a new SzResult.cs and changed Evaluator and DataHander to utilize it

SzCli/Logger.cs

@@ -5,21 +5,10 @@ namespace SzCli;
 
 public class Logger : ISzLogger
 {
-    private DefaultLocalFileManager _fileManager;
     public bool LogToFile { get; set; } = true;
     public string LogFilePath { get; set; }
     public int LogFileMaxLines { get; set; } = 100;
-
+    
-    public Logger(DefaultLocalFileManager fm)
-    {
-        _fileManager = fm;
-        LogFilePath = Path.Combine(_fileManager.DataPath, "log.txt");
-        AppDomain.CurrentDomain.FirstChanceException += (sender, eventArgs) =>
-        {
-            LogError($"[EXCEPTION] {eventArgs.Exception}");
-        };
-    }
-
     public void Log(string text)
     {
         Console.WriteLine($"{DateTime.UtcNow} : [SZ LOG] {text}");
@@ -41,6 +30,16 @@ public class Logger : ISzLogger
     private void AppendLogFile(string text)
     {
         // TODO: Make sure log file adheres to LogFileMaxLines
+        
+        if (!File.Exists(LogFilePath))
+        {
+            LogFilePath = Path.Combine(SZ.LocalFileManager.DataPath, "log.txt");
+            AppDomain.CurrentDomain.FirstChanceException += (sender, eventArgs) =>
+            {
+                LogError($"[EXCEPTION] {eventArgs.Exception}");
+            };
+        }
+        
         File.AppendAllText(LogFilePath, text + "\n");
     }
 }

SzCli/Program.cs

@@ -7,253 +7,12 @@ namespace SzCli;
 
 public class Program
 {
-    private static readonly DefaultLocalFileManager _fileManager = new();
+    private static readonly DefaultLocalFileManager FileManager = new();
-    private static readonly Logger _logger = new(_fileManager);
+    private static readonly Logger Logger = new();
-    private static readonly DefaultDatabaseHandler _dbHandler = new();
+    private static readonly DefaultDatabaseHandler DbHandler = new();
     
     public static void Main(string[] args)
     {
-        SZ.Init(_fileManager, _logger, _dbHandler);
+        SZ.Init(FileManager, Logger, DbHandler);
-
-        bool shouldClose = false;
-
-        while (!shouldClose)
-        {
-            Console.WriteLine(" -- SZ CLI MAIN MENU -- ");
-            Console.WriteLine("0: Exit");
-            Console.WriteLine("1: Create Template");
-            Console.WriteLine("2: Create Dataset");
-            Console.WriteLine("3: Evaluate Dataset");
-            Console.WriteLine("4: Delete Template");
-            Console.WriteLine("5: Delete Dataset");
-            // Console.WriteLine("6: Fetch Template");
-            // Console.WriteLine("7: Fetch Dataset");
-            
-            Console.Write("> ");
-            var userInput = Console.ReadLine();
-            if (!int.TryParse(userInput, out var result))
-            {
-                Console.WriteLine($"Input was not a number, please try again.\n\n");
-                continue;
-            }
-
-            switch (result)
-            {
-                case 0:
-                    shouldClose = true;
-                    break;
-                case 1: 
-                    CreateTemplate();
-                    break;
-                case 2:
-                    CreateDataset();
-                    break;
-                case 3:
-                    EvaluateDataset();
-                    break;
-                case 4:
-                    DeleteTemplate();
-                    break;
-                case 5:
-                    DeleteDataset();
-                    break;
-                default:
-                    Console.WriteLine("Invalid input, please try again");
-                    break;
-            }
-        }
-
-        Console.WriteLine("\n\n");
-    }
-
-    private static void DeleteDataset()
-    {
-        Console.Write("Dataset ID: ");
-        var userInput = Console.ReadLine();
-        if (string.IsNullOrEmpty(userInput))
-        {
-            Console.WriteLine("Id was null");
-            return;
-        }
-        SZ.SzDataHandler.DeleteDataset(userInput);
-    }
-
-    private static void DeleteTemplate()
-    {
-        Console.Write("Template ID: ");
-        var userInput = Console.ReadLine();
-        if (string.IsNullOrEmpty(userInput))
-        {
-            Console.WriteLine("Id was null");
-            return;
-        }
-        SZ.SzDataHandler.DeleteTemplate(userInput);
-    }
-
-    private static void EvaluateDataset()
-    {
-        Console.Write("Dataset ID: ");
-        var userInput = Console.ReadLine();
-        if (string.IsNullOrEmpty(userInput))
-        {
-            Console.WriteLine("Id was null");
-            return;
-        }
-        var dataset = SZ.SzDataHandler.LoadDataset(userInput);
-        if (dataset is null)
-        {
-            Console.WriteLine($"Dataset with ID {userInput} could not be loaded");
-            return;
-        }
-        
-        var evalResult = SZ.SzEvaluator.EvaluateDataset(dataset);
-    }
-
-    private static void CreateDataset()
-    {
-        Console.Write("Enter a name for the dataset: ");
-        var nameInput = Console.ReadLine();
-        if (string.IsNullOrEmpty(nameInput))
-        {
-            Console.WriteLine("Dataset name can't be blank");
-            return;
-        }
-
-        var id = nameInput.ToLower().Replace(" ", "-").Trim();
-
-        Console.Write("Enter template ID: ");
-        var templateIdInput = Console.ReadLine();
-        if (string.IsNullOrEmpty(templateIdInput))
-        {
-            Console.WriteLine("Template ID can't be blank");
-            return;
-        }
-
-        var template = SZ.SzDataHandler.LoadTemplate<SzDataObjectTemplate>(templateIdInput);
-        if (template is null)
-        {
-            Console.WriteLine($"Could not load template with ID {templateIdInput}");
-            return;
-        }
-
-        
-
-
-    }
-
-    private static void CreateTemplate()
-    {
-        Console.Write("Enter a name for the template: ");
-        var nameInput = Console.ReadLine();
-        if (string.IsNullOrEmpty(nameInput))
-        {
-            Console.WriteLine("Template name can't be blank");
-            return;
-        }
-
-        var id = nameInput.ToLower().Replace(" ", "-").Trim();
-
-        Console.Write("Enter a data type for the template: ");
-        var dataTypeInput = Console.ReadLine();
-        if (string.IsNullOrEmpty(dataTypeInput))
-        {
-            Console.WriteLine("Template Data Type can't be blank");
-            return;
-        }
-
-        Console.Write("Enter a description for the template: ");
-        var descInput = Console.ReadLine();
-
-        var fields = CreateTemplateFields();
-
-        var newTemplate = new SzDataObjectTemplate()
-        {
-            Name = nameInput,
-            Id = id,
-            DataObjectType = dataTypeInput,
-            Description = descInput ?? "",
-        };
-
-        foreach (var f in fields)
-        {
-            newTemplate.TemplateFields.Add(f.Id, f);
-        }
-
-        SZ.SzDataHandler.SaveTemplate(newTemplate);
-
-    }
-
-    private static List<SzTemplateField> CreateTemplateFields()
-    {
-        bool done = false;
-        int i = 0;
-        List<SzTemplateField> list = [];
-        while (!done)
-        {
-            i++;
-            Console.Write($"Field {i} ID: ");
-            var idInput = Console.ReadLine();
-            if (string.IsNullOrEmpty(idInput))
-            {
-                Console.WriteLine("Field id can't be blank");
-                i--;
-                continue;
-            }
-
-            if (list.Any(f => f.Id == idInput))
-            {
-                Console.WriteLine($"Field id '{idInput}' must be unique");
-                i--;
-                continue;
-            }
-
-            Console.WriteLine($"Field {idInput} type: ");
-            int enumIter = 0;
-            foreach (var enumType in Enum.GetValues<SzFieldType>())
-            {
-                Console.WriteLine($"- {enumType}");
-                enumIter++;
-            }
-            Console.Write("> ");
-            var typeInput = Console.ReadLine();
-            if (!Enum.TryParse<SzFieldType>(typeInput, out var typeEnumResult))
-            {
-                Console.WriteLine("Field type input was invalid");
-                i--;
-                continue;
-            }
-
-            // Console.Write("Is the field a list?: ");
-            // var isListInput = Console.ReadLine();
-            // if (!bool.TryParse(isListInput, out var isListResult))
-            // {
-            //     Console.WriteLine("Field isList input was invalid");
-            //     i--;
-            //     continue;
-            // }
-
-            Console.Write("Add another field? ");
-            var contInput = Console.ReadLine();
-            switch (contInput)
-            {
-                case "n":
-                case "N":
-                default:
-                    done = true;
-                    break;
-                case "y":
-                case "Y":
-                    break;
-            }
-
-            var newField = new SzTemplateField(){
-                Id = idInput,
-                FieldType = typeEnumResult
-            };
-
-            list.Add(newField);
-        }
-
-        return list;
     }
 }

SzCli/Test.cs

@@ -28,7 +28,7 @@ public static class Test
 
             dt.TemplateFields.Add(testTemplateField.Id, testTemplateField);
 
-            SZ.SzDataHandler.SaveTemplate(dt);
+            SZ.DataHandler.SaveTemplate(dt);
 
             var ds = new SzDataset()
             {
@@ -56,7 +56,7 @@ public static class Test
             testDataObject.Fields.Add(testField.Id, testField);
             ds.DataObjects.Add(testDataObject.Id, testDataObject);
             
-            SZ.SzDataHandler.SaveDataset(ds);
+            SZ.DataHandler.SaveDataset(ds);
         }
         catch (Exception e)
         {

SzCore/SZ.cs

@@ -10,9 +10,9 @@ public static class SZ
 
     public static bool IsInitalized { get; private set; } = false;
 
-    public static readonly SzParser SzParser = new();
+    public static readonly SzParser Parser = new();
-    public static readonly SzDataHandler SzDataHandler = new();
+    public static readonly SzDataHandler DataHandler = new();
-    public static readonly SzEvaluator SzEvaluator = new();
+    public static readonly SzEvaluator Evaluator = new();
 
     public static ISzFileManager LocalFileManager 
     { 
@@ -44,14 +44,15 @@ public static class SZ
         }
     }
 
-    private static readonly Dictionary<Type, object> _services = [];
+    private static readonly Dictionary<Type, object> Services = [];
-    private static readonly List<Type> _protectedServices = [];
+    private static readonly List<Type> ProtectedServices = [];
 
     /// <summary>
     /// Initalizes the SZ singleton in SzCore
     /// </summary>
     /// <param name="fileManager">An ISzFileManager instance.</param>
     /// <param name="logger">An ISzLogger instance.</param>
+    /// <param name="databaseHandler">An ISzDatabaseHandler instance</param>
     /// /// <exception cref="Exception">Throws if SZ has already been initalized</exception>
     public static void Init(ISzFileManager fileManager, ISzLogger logger, ISzDatabaseHandler databaseHandler) 
     {
@@ -96,14 +97,14 @@ public static class SZ
     {
         CheckInitialization();
 
-        var result = _services.TryAdd(instance.GetType(), instance);
+        var result = Services.TryAdd(instance.GetType(), instance);
         if (!result) return false;
 
         if (isProtected)
         {
-            if (_protectedServices.Contains(instance.GetType())) return false;
+            if (ProtectedServices.Contains(instance.GetType())) return false;
 
-            _protectedServices.Add(instance.GetType());
+            ProtectedServices.Add(instance.GetType());
         }
 
         return result;
@@ -113,16 +114,16 @@ public static class SZ
     {
         CheckInitialization();
 
-        if (!_services.ContainsKey(typeof(T))) return default;
+        if (!Services.ContainsKey(typeof(T))) return default;
-        return (T)_services[typeof(T)];
+        return (T)Services[typeof(T)];
     }
 
     public static bool RemoveService<T>()
     {
         CheckInitialization();
 
-        if (_protectedServices.Contains(typeof(T))) return false;
+        if (ProtectedServices.Contains(typeof(T))) return false;
-        return _services.Remove(typeof(T));
+        return Services.Remove(typeof(T));
     }
 
     private static void CheckInitialization()

SzCore/SzDataHandler.cs

@@ -10,7 +10,6 @@ public class SzDataHandler
 
     public SzDataHandler(){}
 
-    // The client should periodically call this to free memory, probably
     private void ClearCache()
     {
         _loadedDatasets.Clear();
@@ -18,39 +17,40 @@ public class SzDataHandler
     }
 
     #region Datasets
-    public bool SaveDataset(SzDataset dataset)
+    public SzResult<bool> SaveDataset(SzDataset dataset)
     {
         var datasetPath = Path.Combine(SZ.LocalFileManager.DatasetsPath, dataset.Id, "dataset.json");
         try
         {
-            return SZ.LocalFileManager.SaveFile(datasetPath, SZ.SzParser.SerializeDatasetToJson(dataset));
+            var success = SZ.LocalFileManager.SaveFile(datasetPath, SZ.Parser.SerializeDatasetToJson(dataset));
+            return success ? SzResult<bool>.Success(true) : SzResult<bool>.Failure("Failed to write dataset file.");
         }
         catch (Exception e)
         {
             SZ.Logger.LogError("Error saving dataset: " + e.Message);
-            return false;
+            return SzResult<bool>.Failure(e.Message);
         }
     }
 
-    public bool DeleteDataset(string datasetId)
+    public SzResult<bool> DeleteDataset(string datasetId)
     {
         try
         {
             Directory.Delete(Path.Combine(SZ.LocalFileManager.DatasetsPath, datasetId), true);
-            return true;
+            return SzResult<bool>.Success(true);
         }
         catch (Exception e)
         {
             SZ.Logger.LogError($"Could not delete Dataset with id '{datasetId}': {e.Message}");
-            return false;
+            return SzResult<bool>.Failure(e.Message);
         }
     }
 
-    public SzDataset? LoadDataset(string datasetId)
+    public SzResult<SzDataset> LoadDataset(string datasetId)
     {
         if (_loadedDatasets.TryGetValue(datasetId, out SzDataset? value))
         {
-            return value;
+            return SzResult<SzDataset>.Success(value);
         }
 
         var datasetPath = Path.Combine(SZ.LocalFileManager.DataPath, "datasets", datasetId, "dataset.json");
@@ -59,61 +59,78 @@ public class SzDataHandler
         if (json is null) 
         {
             SZ.Logger.LogWarning($"Could not load dataset with ID '{datasetId}'");
-            return null;  
+            return SzResult<SzDataset>.Failure($"Could not find dataset file for ID '{datasetId}'");  
         }
 
-        var parsedDataset = SZ.SzParser.DeserializeDataset(json);
+        var parsedDataset = SZ.Parser.DeserializeDataset(json);
         if (parsedDataset is null)
         {
             SZ.Logger.LogWarning($"Could not load dataset with ID '{datasetId}'");
-            return null;  
+            return SzResult<SzDataset>.Failure($"Failed to parse dataset JSON for ID '{datasetId}'");  
         }
 
         _loadedDatasets.Add(parsedDataset.Id, parsedDataset);
-        return parsedDataset;
+        return SzResult<SzDataset>.Success(parsedDataset);
     }
 
-    public SzDataset CreateDataset()
+    public SzResult<SzDataset> CreateDataset(string name, string templateId, string? id = null, Guid? templateUuid = null)
     {
+        if (string.IsNullOrEmpty(name))
+            return SzResult<SzDataset>.Failure("Dataset name cannot be empty.");
 
+        var templateResult = LoadTemplate<SzDataObjectTemplate>(templateId);
+        if (!templateResult.IsSuccess || templateResult.Value is null)
+            return SzResult<SzDataset>.Failure($"Template '{templateId}' not found.");
+
+        var newDataset = new SzDataset()
+        {
+            Name = name,
+            Id = id ?? name.ToLower().Replace(" ", "-").Trim(),
+            DataObjectTemplateId = templateResult.Value.Id,
+            DataObjectTemplateUuid = templateUuid,
+            DataObjectType = templateResult.Value.DataObjectType,
+            Uuid = Guid.NewGuid()
+        };
+
+        return SzResult<SzDataset>.Success(newDataset);
     }
-
     #endregion
 
     #region Templates
-    public bool SaveTemplate(ISzTemplate template)
+    public SzResult<bool> SaveTemplate(ISzTemplate template)
     {
         var templatePath = Path.Combine(SZ.LocalFileManager.TemplatesPath, template.Id, "template.json");
         try
         {
-            return SZ.LocalFileManager.SaveFile(templatePath, SZ.SzParser.SerializeTemplateToJson(template));
+            var success = SZ.LocalFileManager.SaveFile(templatePath, SZ.Parser.SerializeTemplateToJson(template));
+            return success ? SzResult<bool>.Success(true) : SzResult<bool>.Failure("Failed to write template file.");
         }
         catch (Exception e)
         {
             SZ.Logger.LogError("Error saving template: " + e.Message);
-            return false;
+            return SzResult<bool>.Failure(e.Message);
         }
     }
 
-    public bool DeleteTemplate(string templateId)
+    public SzResult<bool> DeleteTemplate(string templateId)
     {
         try
         {
             Directory.Delete(Path.Combine(SZ.LocalFileManager.TemplatesPath, templateId), true);
-            return true;
+            return SzResult<bool>.Success(true);
         }
         catch (Exception e)
         {
             SZ.Logger.LogError($"Could not delete Template with id '{templateId}': {e.Message}");
-            return false;
+            return SzResult<bool>.Failure(e.Message);
         }
     }
 
-    public T? LoadTemplate<T>(string templateId) where T : ISzTemplate
+    public SzResult<T> LoadTemplate<T>(string templateId) where T : ISzTemplate
     {
-        if (_loadedTemplates.TryGetValue(templateId, out ISzTemplate? existing))
+        if (_loadedTemplates.TryGetValue(templateId, out ISzTemplate? cachedTemplate))
         {
-            return (T)existing;
+            return SzResult<T>.Success((T)cachedTemplate);
         }
 
         var templatePah = Path.Combine(SZ.LocalFileManager.TemplatesPath, templateId, "template.json");
@@ -121,63 +138,50 @@ public class SzDataHandler
         var json = SZ.LocalFileManager.LoadFile(templatePah);
         if (json is null) 
         {
-            SZ.Logger.LogWarning($"Could not load tetmplate with ID '{templateId}'");
+            SZ.Logger.LogWarning($"Could not load template with ID '{templateId}'");
-            return default;  
+            return SzResult<T>.Failure($"Could not find template file for ID '{templateId}'");  
         }
 
-        var parsedTemplate = SZ.SzParser.DeserializeTemplate<T>(json);
+        var parsedTemplate = SZ.Parser.DeserializeTemplate<T>(json);
         if (parsedTemplate is null)
         {
             SZ.Logger.LogWarning($"Could not load template with ID '{templateId}'");
-            return default;  
+            return SzResult<T>.Failure($"Failed to parse template JSON for ID '{templateId}'");  
         }
 
         _loadedTemplates.TryAdd(parsedTemplate.Id, parsedTemplate);
 
-        return parsedTemplate;
+        return SzResult<T>.Success(parsedTemplate);
     }
 
-    public SzDataObjectTemplate? CreateDataObjectTemplate(string name, string dataObjectType, string? id = null, string? description = null, List<SzTemplateField>? fields = null)
+    public SzResult<SzDataObjectTemplate> CreateDataObjectTemplate(string name, string dataObjectType, string? id = null, string? description = null, List<SzTemplateField>? fields = null)
     {
-        if (string.IsNullOrEmpty(name) || string.IsNullOrEmpty(dataObjectType)) return null;
+        if (string.IsNullOrEmpty(name)) return SzResult<SzDataObjectTemplate>.Failure("Name cannot be empty.");
-
+        if (string.IsNullOrEmpty(dataObjectType)) return SzResult<SzDataObjectTemplate>.Failure("DataObjectType cannot be empty.");
-        string newId;
-        if (!string.IsNullOrEmpty(id))
-        {
-            newId = id;
-        }
-        else 
-        {
-            newId = name.ToLower().Replace(" ", "-").Trim();
-        }
 
         var newTemplate = new SzDataObjectTemplate()
         {
             Name = name,
-            Id = newId,
+            Id = id ?? name.ToLower().Replace(" ", "-").Trim(),
             DataObjectType = dataObjectType,
             Uuid = Guid.NewGuid(),
             Description = description ?? ""
         };
 
-        if (fields is not null)
+        if (fields is null) return SzResult<SzDataObjectTemplate>.Success(newTemplate);
+        foreach (var field in fields)
         {
-            foreach (var field in fields)
+            newTemplate.TemplateFields.Add(field.Id, field);    
-            {
-                newTemplate.TemplateFields.Add(field.Id, field);    
-            }
         }
 
-        return newTemplate;
+        return SzResult<SzDataObjectTemplate>.Success(newTemplate);
-
     }
     #endregion
 
     #region Other
-
+    public SzResult<SzTemplateField> CreateTemplateField(string id, SzFieldType fieldType, bool isList = false, string? defaultValue = null, bool isSpecialType = false, string? specialTypeValue = null)
-    public SzTemplateField? CreateTemplateField(string id, SzFieldType fieldType, bool isList = false, string? defaultValue = null, bool isSpecialType = false, string? specialTypeValue = null)
     {
-        if (string.IsNullOrEmpty(id)) return null;
+        if (string.IsNullOrEmpty(id)) return SzResult<SzTemplateField>.Failure("ID cannot be empty.");
 
         var newField = new SzTemplateField()
         {
@@ -189,13 +193,21 @@ public class SzDataHandler
             SpecialTypeValue = specialTypeValue ?? ""
         };
 
-        return newField;
+        return SzResult<SzTemplateField>.Success(newField);
     }
 
+    public SzResult<List<SzField>> CreateFields(ISzTemplate template) 
+    {
+        return SzResult<List<SzField>>.Failure("Not implemented");
+    }
+
+    public SzResult<SzDataObject> CreateDataObject() 
+    {
+        return SzResult<SzDataObject>.Failure("Not implemented");
+    }
     #endregion
 
     #region Tests
-    // Only use these two methods for test purposes, we probably don't want to load all datasets and templates to memory in production
     private void LoadAllDatasets()
     {
         _loadedDatasets.Clear();
@@ -212,7 +224,7 @@ public class SzDataHandler
             var datasetJson = SZ.LocalFileManager.LoadFile(datasetFilePath);
             if (datasetJson == null) continue;
 
-            var parsedDataset = SZ.SzParser.DeserializeDataset(datasetJson);
+            var parsedDataset = SZ.Parser.DeserializeDataset(datasetJson);
             if (parsedDataset == null)
             {
                 SZ.Logger.LogWarning($"Parse error: Could not parse file {datasetFilePath} as an SzDataset");
@@ -239,7 +251,7 @@ public class SzDataHandler
             var templateJson = SZ.LocalFileManager.LoadFile(templateFilePath);
             if (templateJson == null) continue;
 
-            var parsedTemplate = SZ.SzParser.DeserializeTemplate<ISzTemplate>(templateJson);
+            var parsedTemplate = SZ.Parser.DeserializeTemplate<ISzTemplate>(templateJson);
             if (parsedTemplate == null)
             {
                 SZ.Logger.LogWarning($"Parse error: Could not parse file {templateFilePath} as an ISzTemplate");

SzCore/SzEvaluator.cs

@@ -7,29 +7,25 @@ namespace SzCore;
 public class SzEvaluator
 {
 
-    public SzOperationResult EvaluateDataset(SzDataset dataset)
+    public SzResult<bool> EvaluateDataset(SzDataset dataset)
     {
-        if (dataset is null) return new SzOperationResult(false, "Dataset cannot be null");
-
         var errors = new StringBuilder();
 
-        var template = SZ.SzDataHandler.LoadTemplate<SzDataObjectTemplate>(dataset.DataObjectTemplateId);
+        var template = SZ.DataHandler.LoadTemplate<SzDataObjectTemplate>(dataset.DataObjectTemplateId);
-        if (template is null) return new SzOperationResult(false, $"Template with id {dataset.DataObjectTemplateId} for Dataset ID {dataset.Id} could not be loaded");
+        if (!template.IsSuccess || template.Value is null) return SzResult<bool>.Failure($"Template with id {dataset.DataObjectTemplateId} for Dataset ID {dataset.Id} could not be loaded");
 
         foreach (var dataObject in dataset.DataObjects.Values)
         {
-            var evalResult = EvaluateDataObject(dataObject, template);
+            var evalResult = EvaluateDataObject(dataObject, template.Value);
-            if (!evalResult.Pass) errors.Append(evalResult.Errors);
+            if (!evalResult.IsSuccess) errors.Append(evalResult.Error);
         }
 
         var errString = errors.ToString();
-        return new SzOperationResult(string.IsNullOrEmpty(errString), errString);
+        return string.IsNullOrEmpty(errString) ? SzResult<bool>.Success(true) : SzResult<bool>.Failure(errString);
     }
 
-    public SzOperationResult EvaluateDataObject(SzDataObject dataObject, SzDataObjectTemplate template)
+    public SzResult<bool> EvaluateDataObject(SzDataObject dataObject, SzDataObjectTemplate template)
     {
-        if (dataObject is null || template is null) return new SzOperationResult(false, "dataObject or template is null");
-
         var errors = new StringBuilder();
 
         foreach (var (key, templateField) in template.TemplateFields)
@@ -41,10 +37,10 @@ public class SzEvaluator
             }
 
             var templateMatchResult = DoesFieldMatchTemplateField(matchingField, templateField);
-            if (!templateMatchResult.Pass) errors.Append(templateMatchResult.Errors);
+            if (!templateMatchResult.IsSuccess) errors.Append(templateMatchResult.Error);
 
             var evalResult = EvaluateFieldValue(matchingField);
-            if (!evalResult.Pass) errors.Append(evalResult.Errors);
+            if (!evalResult.IsSuccess) errors.Append(evalResult.Error);
         }
 
         foreach (var objectFieldKey in dataObject.Fields.Keys)
@@ -56,10 +52,10 @@ public class SzEvaluator
         }
 
         var errString = errors.ToString().Trim();
-        return new SzOperationResult(string.IsNullOrEmpty(errString), string.IsNullOrEmpty(errString) ? "" : errString);
+        return string.IsNullOrEmpty(errString) ? SzResult<bool>.Success(true) : SzResult<bool>.Failure(errString);
     }
 
-    public SzOperationResult DoesFieldMatchTemplateField(SzField field, SzTemplateField templateField)
+    public SzResult<bool> DoesFieldMatchTemplateField(SzField field, SzTemplateField templateField)
     {
         var errors = new StringBuilder();
 
@@ -68,13 +64,13 @@ public class SzEvaluator
         if (field.IsList != templateField.IsList) errors.AppendLine($"Field '{field.Id}' IsList mismatch: Expected {templateField.IsList}");
 
         var errString = errors.ToString().Trim();
-        return new SzOperationResult(string.IsNullOrEmpty(errString), errString);
+        return string.IsNullOrEmpty(errString) ? SzResult<bool>.Success(true) : SzResult<bool>.Failure(errString);
     }
 
-    public SzOperationResult EvaluateFieldValue(SzField field)
+    public SzResult<bool> EvaluateFieldValue(SzField field)
     {
         if (string.IsNullOrWhiteSpace(field.Value)) 
-            return new SzOperationResult(true, "");
+            return SzResult<bool>.Success(true);
 
         var errors = new StringBuilder(); 
 
@@ -111,6 +107,6 @@ public class SzEvaluator
         }
 
         var errString = errors.ToString().Trim();
-        return new SzOperationResult(string.IsNullOrEmpty(errString), errString);
+        return string.IsNullOrEmpty(errString) ? SzResult<bool>.Success(true) : SzResult<bool>.Failure(errString);
     }
-} 
+}

SzCore/SzException.cs

@@ -0,0 +1,8 @@
+namespace SzCore;
+
+public class SzException : Exception
+{
+    public SzException() {}
+    public SzException(string message) : base (message) {}
+    public SzException(string message, Exception inner) : base(message, inner) {}
+}

SzCore/SzOperationResult.cs

@@ -1,7 +0,0 @@
-namespace SzCore;
-
-public class SzOperationResult(bool pass, string errors = "None")
-{
-    public bool Pass = pass;
-    public string Errors = errors;
-}

SzCore/SzResult.cs

@@ -0,0 +1,14 @@
+namespace SzCore;
+
+public class SzResult<T>
+{
+    public bool IsSuccess { get; }
+    public T? Value { get; }
+    public string? Error { get; }
+
+    protected SzResult(T? value, bool success, string? error) 
+        => (Value, IsSuccess, Error) = (value, success, error);
+
+    public static SzResult<T> Success(T value) => new(value, true, null);
+    public static SzResult<T> Failure(string error) => new(default, false, error);
+}