private VisitResult VisitFunctionCall(ASTFunctionCall functionCall)
{
var symbolFunction = functionCall.SymbolFunction;
var functionName = functionCall.FunctionName;
var formalParameters = symbolFunction.Parameters;
var actualParameters = functionCall.ActualParameters;
var activationRecord = new ActivationRecord(functionName, ActivationRecordType.Function, symbolFunction.ScopeLevel + 1);
for (var i = 0; i < formalParameters.Count; ++i)
{
activationRecord[formalParameters[i].Name] = Visit(actualParameters[i]).Value;
}
Logger.Debug($"Enter {functionName}");
_callStack.Push(activationRecord);
var result = symbolFunction is SymbolBuiltinFunction?BuiltinFunctionCall(functionCall) : Visit(symbolFunction.Body);
var returnedValue = result != null ? result.Value : "null";
if (returnedValue is List <dynamic> collection)
{
returnedValue = collection.ToPrint();
}
Logger.DebugMemory($"Leave {functionName}, returned value ({returnedValue})");
Logger.DebugMemory(_callStack.ToString());
_callStack.Pop();
return(result);
}
private VisitResult BuiltinFunctionCall(ASTFunctionCall functionCall)
{
var functionName = functionCall.FunctionName;
switch (functionName)
{
case "print":
return(PrintFunctionCall());
}
throw new ArgumentNullException($"Builtin function {functionName} not found");
}
private static ASTNode ParseFunctionCallOrParameterAccess(string scope)
{
string functionNameOrParameter = currentTokens[currentToken].Token;
currentToken++;
if (currentTokens[currentToken].Token != "(")
{
return(new ASTClassParameter()
{
Scope = scope,
Parameter = new ASTStatement()
{
Statement = new ASTString()
{
String = functionNameOrParameter
}
}
});
}
currentToken++;
ASTFunctionCall ret = new ASTFunctionCall()
{
Scope = scope,
FunctionName = functionNameOrParameter
};
while (currentTokens[currentToken].Token != ")")
{
ret.Parameter.Add(ParseStatement());
if (currentTokens[currentToken].Token == ",")
{
currentToken++;
}
}
currentToken++;
return(ret);
}
private dynamic VisitProgram(ASTProgram program)
{
Logger.Debug("Enter Program");
var activationRecord = new ActivationRecord("Main", ActivationRecordType.Program, 1);
_callStack.Push(activationRecord);
var runParameters = new List <ASTNode>();
var mainFunction = new ASTFunctionCall(program.Token, "Main", runParameters);
mainFunction.SymbolFunction = program.MainFunction;
var result = Visit(mainFunction);
Logger.DebugMemory("Leave Program");
Logger.DebugMemory(_callStack.ToString());
_callStack.Pop();
Logger.Debug($"Program exited with status code {result?.Value ?? "null"}");
return(result);
}
private static ASTNode ParseSingleStatement()
{
ASTNode ret = null;
if (currentTokens[currentToken] is StringToken)
{
ret = new ASTString {
String = currentTokens[currentToken].Token
};
currentToken++;
}
else if (currentTokens[currentToken] is NumberToken)
{
double dResult;
if (double.TryParse(currentTokens[currentToken].Token, NumberStyles.Any, CultureInfo.GetCultureInfo("en"), out dResult))
{
ret = new ASTNumber {
Number = dResult
};
}
else
{
throw new ParserException(string.Format("Number {0} is not valid.", currentTokens[currentToken].Token), currentTokens[currentToken].LineNumber);
}
currentToken++;
}
else if (currentTokens[currentToken] is ReservedWordToken)
{
if (currentTokens[currentToken].Token == "this" || currentTokens[currentToken].Token == "VM")
{
string scope = currentTokens[currentToken].Token;
currentToken++;
if (currentTokens[currentToken] is SpecialToken && currentTokens[currentToken].Token == ".")
{
currentToken++;
ret = ParseFunctionCallOrParameterAccess(scope);
}
else
{
throw new ParserException(string.Format("Expected '.' instead of '{0}'.", currentTokens[currentToken].Token), currentTokens[currentToken].LineNumber);
}
}
else if (currentTokens[currentToken].Token == "object" ||
currentTokens[currentToken].Token == "string" ||
currentTokens[currentToken].Token == "number")
{
VMType type = currentTokens[currentToken].Token == "number" ? VMType.Number : (currentTokens[currentToken].Token == "string" ? VMType.String : VMType.Object);
currentToken++;
if (currentTokens[currentToken] is IdentifierToken)
{
ret = new ASTLocalVariable()
{
Type = type,
Name = currentTokens[currentToken].Token
};
}
else
{
throw new ParserException("Expected Identifier.", currentTokens[currentToken].LineNumber);
}
currentToken++;
}
else if (currentTokens[currentToken].Token == "new")
{
currentToken++;
ASTNode createClass = ParseFunctionCallOrParameterAccess("constructor");
if (createClass is ASTFunctionCall)
{
ASTFunctionCall fc = (ASTFunctionCall)createClass;
ret = new ASTCreateClass()
{
Scope = fc.FunctionName,
FunctionName = fc.FunctionName,
Parameter = fc.Parameter
};
}
else
{
throw new ParserException("Error with new.", currentTokens[currentToken].LineNumber);
}
}
else if (currentTokens[currentToken].Token == "return")
{
currentToken++;
ret = new ASTReturn()
{
Return = ParseStatement()
};
// Point to ';' again!!!
--currentToken;
}
else
{
throw new ParserException(string.Format("Reserved Word {0} is not legal in Statement.", currentTokens[currentToken].Token), currentTokens[currentToken].LineNumber);
}
}
else if (currentTokens[currentToken] is IdentifierToken)
{
string identifierOrScope = currentTokens[currentToken].Token;
currentToken++;
if (currentTokens[currentToken] is SpecialToken)
{
if (currentTokens[currentToken].Token == ".")
{
currentToken++;
TokenBase isFunction = currentTokens[currentToken + 1];
ret = ParseFunctionCallOrParameterAccess(identifierOrScope);
}
else if (currentTokens[currentToken].Token == "(")
{
// Set focus again to the function name
--currentToken;
ret = ParseFunctionCallOrParameterAccess("this");
}
else if (currentTokens[currentToken].Token == "[")
{
currentToken++;
ASTStatement statement = ParseStatement();
if (statement == null)
{
throw new ParserException("Expected Statement for Parameter Access.", currentTokens[currentToken].LineNumber);
}
ret = new ASTClassParameter()
{
Scope = identifierOrScope,
Parameter = statement
};
}
else
{
ret = new ASTIdentifier()
{
Identifier = identifierOrScope
};
}
}
else
{
ret = new ASTIdentifier()
{
Identifier = identifierOrScope
};
}
}
if (ret == null)
{
throw new ParserException(String.Format("Problems parsing the Identifier/Function Call/String/Number {0}.", currentTokens[currentToken].Token), currentTokens[currentToken].LineNumber);
}
return(ret);
}
private static void PrintNode(ASTNode node, int incident)
{
if (node == null)
{
return;
}
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
if (node is ASTString)
{
sw.WriteLine("ASTString: " + ((ASTString)node).String.Replace("\n", "\\n"));
}
else if (node is ASTNumber)
{
sw.WriteLine("ASTNumber: " + ((ASTNumber)node).Number);
}
else if (node is ASTIdentifier)
{
sw.WriteLine("ASTIdentifier: " + ((ASTIdentifier)node).Identifier);
}
else if (node is ASTOperator)
{
ASTOperator op = (ASTOperator)node;
sw.WriteLine("ASTOperator: " + op.Operator);
PrintNode(op.Left, incident + 1);
PrintNode(op.Right, incident + 1);
}
else if (node is ASTStatement)
{
ASTStatement stm = (ASTStatement)node;
sw.WriteLine("ASTStatement: ");
PrintNode(stm.Statement, incident + 1);
}
else if (node is ASTFunctionCall)
{
ASTFunctionCall call = (ASTFunctionCall)node;
sw.WriteLine("ASTFunctionCall: " + call.Scope + "." + call.FunctionName);
foreach (ASTNode param in call.Parameter)
{
PrintNode(param, incident + 1);
}
}
else if (node is ASTClassParameter)
{
ASTClassParameter classP = (ASTClassParameter)node;
sw.WriteLine("ASTClassParameter: " + classP.Scope);
PrintNode(classP.Parameter, incident + 1);
}
else if (node is ASTIf)
{
ASTIf ifNode = (ASTIf)node;
sw.WriteLine("ASTIf:");
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCondition:");
PrintNode(ifNode.Condition, incident + 2);
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCodeBlock:");
foreach (ASTNode codeBlock in ifNode.CodeBlock)
{
PrintNode(codeBlock, incident + 2);
}
if (ifNode.ElseCodeBlock != null)
{
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tElse:");
foreach (ASTNode codeBlock in ifNode.ElseCodeBlock)
{
PrintNode(codeBlock, incident + 2);
}
}
}
else if (node is ASTFor)
{
ASTFor forNode = (ASTFor)node;
sw.WriteLine("ASTFor:");
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tInit:");
PrintNode(forNode.Initialise, incident + 2);
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCondition:");
PrintNode(forNode.Condition, incident + 2);
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCounter:");
PrintNode(forNode.Count, incident + 2);
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCodeBlock:");
foreach (ASTNode codeBlock in forNode.CodeBlock)
{
PrintNode(codeBlock, incident + 2);
}
}
else if (node is ASTWhile)
{
ASTWhile wNode = (ASTWhile)node;
sw.WriteLine("ASTWhile:");
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCondition:");
PrintNode(wNode.Condition, incident + 2);
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCodeBlock:");
foreach (ASTNode codeBlock in wNode.CodeBlock)
{
PrintNode(codeBlock, incident + 2);
}
}
else if (node is ASTFunction)
{
ASTFunction func = (ASTFunction)node;
if (node is ASTConstructor)
{
sw.WriteLine("ASTConstructor:");
}
else
{
sw.WriteLine("ASTFunction: " + func.ReturnValue.ToString() + " " + func.Name);
}
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tParameter:");
foreach (ASTNode n in func.Parameter)
{
PrintNode(n, incident + 2);
}
for (int i = 0; i < incident; i++)
{
sw.Write("\t");
}
sw.WriteLine("\tCodeBlock:");
foreach (ASTNode codeBlock in func.CodeBlock)
{
PrintNode(codeBlock, incident + 2);
}
}
else if (node is ASTFunctionParameter)
{
ASTFunctionParameter param = (ASTFunctionParameter)node;
switch (param.Type)
{
case VMType.Object:
sw.WriteLine("Object: " + param.Name);
break;
case VMType.String:
sw.WriteLine("String: " + param.Name);
break;
case VMType.Number:
sw.WriteLine("Number: " + param.Name);
break;
}
}
else if (node is ASTLocalVariable)
{
ASTLocalVariable param = (ASTLocalVariable)node;
switch (param.Type)
{
case VMType.Object:
sw.WriteLine("var Object: " + param.Name);
break;
case VMType.String:
sw.WriteLine("var String: " + param.Name);
break;
case VMType.Number:
sw.WriteLine("var Number: " + param.Name);
break;
}
}
else if (node is ASTReturn)
{
sw.WriteLine("ASTReturn:");
PrintNode(((ASTReturn)node).Return, incident + 1);
}
else if (node is ASTClass)
{
ASTClass cNode = (ASTClass)node;
sw.WriteLine("ASTClass: " + cNode.Name);
sw.WriteLine("\tAttributes:");
foreach (ASTNode n in cNode.Attributes)
{
PrintNode(n, incident + 2);
}
sw.WriteLine("\tConstructors:");
foreach (ASTNode n in cNode.Constructors)
{
PrintNode(n, incident + 2);
}
sw.WriteLine("\tFunctions:");
foreach (ASTNode n in cNode.Functions)
{
PrintNode(n, incident + 2);
}
}
}