Added some comments, removed unnecessary files

Author: Sergiu Marton

PseudocodeInterpreter/PseudocodeInterpreter.csproj

@@ -57,14 +57,12 @@
     <Compile Include="src\ExtensionMethods.cs" />
     <Compile Include="src\Interpreter.cs" />
     <Compile Include="src\Objects\BooleanLiteral.cs" />
-    <Compile Include="src\Objects\IValue.cs" />
     <Compile Include="src\Objects\Literal.cs" />
     <Compile Include="src\Objects\NumberLiteral.cs" />
     <Compile Include="src\Objects\StringLiteral.cs" />
     <Compile Include="src\Objects\TypeNames.cs" />
     <Compile Include="src\PseudoVisitorImpl.cs" />
     <Compile Include="src\Scope.cs" />
-    <Compile Include="src\SymbolTable.cs" />
   </ItemGroup>
   <ItemGroup>
     <Content Include="src\AntlrFiles\antlr-4.7.1-complete.jar" />

PseudocodeInterpreter/src/Interpreter.cs

@@ -11,9 +11,11 @@ public static class Interpreter
 		public static Action<string> Output { get; set; } = Console.Write;
 		public static Func<string> Input { get; set; } = Console.ReadLine;
 
-		public static void ExecuteFile(string[] args)
+		public static void ExecuteFile(string fileName)
 		{
-			string source = File.ReadAllText(args[0]);
+			string source = File.ReadAllText(fileName);
+
+			// Remove all empty lines
 			source = Regex.Replace(source, @"^\s*$\n|\r", string.Empty, RegexOptions.Multiline).TrimEnd();
 
 			ICharStream input = CharStreams.fromstring(source);
@@ -34,28 +36,5 @@ public static void ExecuteFile(string[] args)
 				Output(e.Message);
 			}
 		}
-
-		public static void ExecuteString(string text)
-		{ 
-			string toExecute = Regex.Replace(text, @"^\s*$\n|\r", string.Empty, RegexOptions.Multiline).TrimEnd();
-
-			ICharStream input = CharStreams.fromstring(toExecute);
-
-			PseudoLexer lexer = new PseudoLexer(input);
-			CommonTokenStream tokens = new CommonTokenStream(lexer);
-			PseudoParser parser = new PseudoParser(tokens);
-			var tree = parser.file();
-
-			PseudoVisitorImpl calcVisitor = new PseudoVisitorImpl();
-
-			try
-			{
-				calcVisitor.Visit(tree);
-			}
-			catch (Exception e)
-			{
-				Output(e.Message);
-			}
-		}
 	}
 }

PseudocodeInterpreter/src/Objects/IValue.cs

@@ -3,13 +3,8 @@
 
 namespace PseudocodeInterpreter.Objects
 {
-    public abstract class Literal : IValue
+    public abstract class Literal
     {
-	    Literal IValue.GetValue()
-	    {
-		    return this;
-	    }
-
 		public string Type { get; protected set; }
 
 	    public virtual bool ToBoolean()

PseudocodeInterpreter/src/Objects/Literal.cs

@@ -6,6 +6,7 @@ class StringLiteral : Literal
 
 	    public StringLiteral(string value)
 	    {
+			// Handle escaped quotes
 		    _value = value.Replace("\\\"", "\"");
 		    Type = TypeNames.StringType;
 	    }

PseudocodeInterpreter/src/Objects/StringLiteral.cs

@@ -7,6 +7,10 @@ namespace PseudocodeInterpreter
 {
 	static class Program
 	{
+		/// <param name="args">
+		/// Represents the command line args. Should be &lt;filename&gt;.
+		/// "diagnostics" is optional but should come after the &lt;filename&gt;
+		/// </param>
 		public static void Main(string[] args)
 		{
 			if (!File.Exists(args[0]))
@@ -20,17 +24,25 @@ public static void Main(string[] args)
 				{
 					Interpreter.Output($"> Se executa {args[0]}{Environment.NewLine}");
 
+					// Start to count execution time
 					Stopwatch stopwatch = Stopwatch.StartNew();
 
-					Interpreter.ExecuteFile(args);
+					Interpreter.ExecuteFile(args[0]);
 
 					stopwatch.Stop();
 
-					Interpreter.Output($"{Environment.NewLine}> Executia a durat: {stopwatch.Elapsed}{Environment.NewLine}");
+					Interpreter.Output(
+						$"{Environment.NewLine}> Executia a durat: {stopwatch.Elapsed}{Environment.NewLine}");
 					Interpreter.Output("> Apasati tasta ENTER pentru a inchide programul...");
+
+					// Ask for ENTER-ending input so the user can see the output of the program before quiting
 					Interpreter.Input();
 				}
 			}
+			else
+			{
+				Interpreter.ExecuteFile(args[0]);
+			}
 		}
 	}
 }

PseudocodeInterpreter/src/Program.cs

@@ -17,6 +17,9 @@ public override object VisitFile(PseudoParser.FileContext context)
 			return null;
 		}
 
+		/// <summary>
+		/// Enter a list/ block of statements, and manages the scope creation for it
+		/// </summary>
 		public override object VisitStatList(PseudoParser.StatListContext context)
 		{
 			_scopes.Push();
@@ -33,6 +36,7 @@ public override object VisitStatList(PseudoParser.StatListContext context)
 
 		public override object VisitIfStat(PseudoParser.IfStatContext context)
 		{
+			// Evaluate the boolean condition
 			var condRes = ((Literal) Visit(context.boolOp())).ToBoolean();
 			if (condRes)
 			{
@@ -75,6 +79,7 @@ public override object VisitForStat(PseudoParser.ForStatContext context)
 			var varType = _scopes.GetVar(varName).Type;
 			Visit(context.varAssign());
 
+			// Loops through the for as long as the incremented variable meets the condition
 			for (
 				float i = (NumberLiteral) _scopes.GetVar(varName);
 				i < (NumberLiteral) Visit(context.expr());
@@ -89,13 +94,15 @@ public override object VisitForStat(PseudoParser.ForStatContext context)
 
 		public override object VisitReadBuiltin(PseudoParser.ReadBuiltinContext context)
 		{
+			// Separate input using spaces into multiple values
 			var values = Interpreter.Input()?.Split(' ');
 
 			if (values == null)
 			{
 				throw new Exception(ErrorMessages.NullInput);
 			}
 
+			// Check if the number of values read is bigger than the number of values requested
 			if (values.Length != context.ID().Length)
 			{
 				throw new Exception(ErrorMessages.ArgumentsNumber);
@@ -108,6 +115,8 @@ public override object VisitReadBuiltin(PseudoParser.ReadBuiltinContext context)
 				{
 					var variable = _scopes.GetVar(ids[i]);
 
+					// Try to fit the value into the type of the variable that requested the value
+
 					if (variable is NumberLiteral numVar)
 					{
 						if (numVar.IsInteger)
@@ -164,6 +173,9 @@ public override object VisitWriteBuiltin(PseudoParser.WriteBuiltinContext contex
 		public override object VisitVariableDeclaration(PseudoParser.VariableDeclarationContext context)
 		{
 			var varType = context.type().GetText();
+
+			// Check for each declaration if it includes initialization or not
+
 			foreach (var optionalAssignContext in context.optionalAssign())
 			{
 				VisitOptionalAssign(optionalAssignContext, varType);
@@ -179,6 +191,8 @@ public object VisitOptionalAssign(PseudoParser.OptionalAssignContext context, st
 			var expr = context.expr();
 			if (expr != null)
 			{
+				// Try to fit the initialization value into the variable
+
 				var exprResult = Visit(expr) as Literal;
 				if (exprResult is NumberLiteral exprNum)
 				{
@@ -214,7 +228,7 @@ public object VisitOptionalAssign(PseudoParser.OptionalAssignContext context, st
 					}
 				}
 			}
-			else
+			else // if the variable is not initialized, assign a default value for its type
 			{
 				if (varType == TypeNames.IntegerType)
 				{
@@ -256,6 +270,8 @@ public override object VisitVarAssign(PseudoParser.VarAssignContext context)
 				throw new Exception(ErrorMessages.UndefinedSymbol(varName));
 			}
 
+			// Try to fit the assigned value into the variable
+
 			var exprResult = (Literal) Visit(context.expr());
 
 			if (exprResult is NumberLiteral exprNum)
@@ -295,14 +311,14 @@ public override object VisitVarAssign(PseudoParser.VarAssignContext context)
 		public override object VisitAndOp(PseudoParser.AndOpContext context)
 		{
 			var leftValue = ((BooleanLiteral) Visit(context.boolOp(0))).ToBoolean();
-			var rightValue = ((BooleanLiteral)Visit(context.boolOp(1))).ToBoolean();
+			var rightValue = ((BooleanLiteral) Visit(context.boolOp(1))).ToBoolean();
 			return new BooleanLiteral(leftValue && rightValue);
 		}
 
 		public override object VisitOrOp(PseudoParser.OrOpContext context)
 		{
-			var leftValue = ((BooleanLiteral)Visit(context.boolOp(0))).ToBoolean();
-			var rightValue = ((BooleanLiteral)Visit(context.boolOp(1))).ToBoolean();
+			var leftValue = ((BooleanLiteral) Visit(context.boolOp(0))).ToBoolean();
+			var rightValue = ((BooleanLiteral) Visit(context.boolOp(1))).ToBoolean();
 			return new BooleanLiteral(leftValue || rightValue);
 		}
 
@@ -327,29 +343,29 @@ public override object VisitAreEqual(PseudoParser.AreEqualContext context)
 
 		public override object VisitGreaterThan(PseudoParser.GreaterThanContext context)
 		{
-			var leftValue = (NumberLiteral)Visit(context.plusOrMinus(0));
-			var rightValue = (NumberLiteral)Visit(context.plusOrMinus(1));
+			var leftValue = (NumberLiteral) Visit(context.plusOrMinus(0));
+			var rightValue = (NumberLiteral) Visit(context.plusOrMinus(1));
 			return new BooleanLiteral(leftValue.Value > rightValue.Value);
 		}
 
 		public override object VisitGreaterOrEqual(PseudoParser.GreaterOrEqualContext context)
 		{
-			var leftValue = (NumberLiteral)Visit(context.plusOrMinus(0));
-			var rightValue = (NumberLiteral)Visit(context.plusOrMinus(1));
+			var leftValue = (NumberLiteral) Visit(context.plusOrMinus(0));
+			var rightValue = (NumberLiteral) Visit(context.plusOrMinus(1));
 			return new BooleanLiteral(leftValue.Value >= rightValue.Value);
 		}
 
 		public override object VisitLessThan(PseudoParser.LessThanContext context)
 		{
-			var leftValue = (NumberLiteral)Visit(context.plusOrMinus(0));
-			var rightValue = (NumberLiteral)Visit(context.plusOrMinus(1));
+			var leftValue = (NumberLiteral) Visit(context.plusOrMinus(0));
+			var rightValue = (NumberLiteral) Visit(context.plusOrMinus(1));
 			return new BooleanLiteral(leftValue.Value < rightValue.Value);
 		}
 
 		public override object VisitLessOrEqual(PseudoParser.LessOrEqualContext context)
 		{
-			var leftValue = (NumberLiteral)Visit(context.plusOrMinus(0));
-			var rightValue = (NumberLiteral)Visit(context.plusOrMinus(1));
+			var leftValue = (NumberLiteral) Visit(context.plusOrMinus(0));
+			var rightValue = (NumberLiteral) Visit(context.plusOrMinus(1));
 			return new BooleanLiteral(leftValue.Value <= rightValue.Value);
 		}
 

PseudocodeInterpreter/src/PseudoVisitorImpl.cs

@@ -45,8 +45,10 @@ public void CreateVariable(string name, Literal value)
 
 		public Literal GetVar(string name)
 		{
+			// Go from the last added scope to the first one
 		    for (int i = _scopes.Count - 1; i >= 0; i--)
             {
+				// Searching for the variable by name
 				if (_scopes[i].Variables.ContainsKey(name))
 				{
 					return _scopes[i].Variables[name];
@@ -58,23 +60,28 @@ public Literal GetVar(string name)
 
 		public void SetVar(string name, Literal value)
 		{
-		    for (int i = _scopes.Count - 1; i >= 0; i--)
+			// Go from the last added scope to the first one
+			for (int i = _scopes.Count - 1; i >= 0; i--)
 		    {
-		        if (_scopes[i].Variables.ContainsKey(name))
+			    // Searching for the variable by name
+				if (_scopes[i].Variables.ContainsKey(name))
 		        {
 		            _scopes[i].Variables[name] = value;
                     return;
 		        }
 		    }
 
+			// The name specified does not define a variable
 			throw new Exception(ErrorMessages.UndefinedSymbol(name));
 		}
 
 		public bool DoesVariableExist(string name)
 		{
-		    for (int i = _scopes.Count - 1; i >= 0; i--)
+			// Go from the last added scope to the first one
+			for (int i = _scopes.Count - 1; i >= 0; i--)
 		    {
-		        if (_scopes[i].Variables.ContainsKey(name))
+			    // Searching for the variable by name
+				if (_scopes[i].Variables.ContainsKey(name))
 		        {
 		            return true;
 		        }