private void assignment(AST tree)
{
string variableName = tree.getChild(0).getTokenString();
AST expression = tree.getChild(1);
ReturnValue expressionValue = execute(expression);
assignValue(variableName, expressionValue);
}
private void ifThenElse(AST tree)
{
// Push scope
AST_IfNode ifNode = (AST_IfNode)(tree);
Assert.IsNotNull(ifNode);
m_currentScope = (Scope)ifNode.getScope();
Assert.IsNotNull(m_currentScope);
// Evaluate conditional
ReturnValue conditionalExpression = execute(tree.getChild(0));
if (conditionalExpression.FloatValue != 0)
{
Assert.IsNotNull(tree.getChild(1));
execute(tree.getChild(1));
}
else
{
if (tree.getChildren().Count == 3)
{
Assert.IsNotNull(tree.getChild(2));
execute(tree.getChild(2));
}
}
// Pop scope
m_currentScope = (Scope)ifNode.getScope().getEnclosingScope();
Assert.IsNotNull(m_currentScope);
}
private void assignment(AST tree)
{
string variableName = tree.getChild(0).getTokenString();
AST expression = tree.getChild(1);
ReturnValue expressionValue = execute(expression);
assignValue(variableName, expressionValue);
}
private void evaluateReferencesForFUNC_DECLARATION(AST tree)
{
string functionName = tree.getChild(1).getTokenString();
m_currentScope = (Scope)m_currentScope.resolve(functionName); // push the scope with the function
#if WRITE_DEBUG_INFO
Console.WriteLine("\n Trying to resolve function parameters and body of " + functionName);
#endif
evaluateReferencesInAllChildren(tree.getChild(2)); // parameters
evaluateReferencesInAllChildren(tree.getChild(3)); // function body
m_currentScope = m_currentScope.getEnclosingScope(); // pop scope
}
private ExternalFunctionCreator AddExternalFunctions(FunctionDefinition[] functionDefinitions, AST ast)
{
List <FunctionDefinition> allFunctionDefinitions = new List <FunctionDefinition>();
allFunctionDefinitions.AddRange(builtInFunctions);
allFunctionDefinitions.AddRange(functionDefinitions);
// HasFunction requires a reference to the SprakRunner
FunctionDocumentation functionDoc_HasFunction =
new FunctionDocumentation("Check if a function exists on the object", new string[] { "The name of the function" });
allFunctionDefinitions.Add(new FunctionDefinition("bool", "HasFunction", new string[] { "string" }, new string[] { "functionName" }, new ExternalFunctionCreator.OnFunctionCall(API_hasFunction), functionDoc_HasFunction));
FunctionDocumentation functionDoc_ListFunctions =
new FunctionDocumentation("List all functions on the object", new string[] { });
allFunctionDefinitions.Add(new FunctionDefinition("array", "ListFunctions", new string[] { }, new string[] { }, new ExternalFunctionCreator.OnFunctionCall(API_listFunction), functionDoc_ListFunctions));
ExternalFunctionCreator externalFunctionCreator = new ExternalFunctionCreator(allFunctionDefinitions.ToArray());
AST functionList = ast.getChild(1);
foreach (AST externalFunction in externalFunctionCreator.FunctionASTs)
{
functionList.addChild(externalFunction);
}
return(externalFunctionCreator);
}
void AddLocalVariables(AST ast, VariableDefinition[] variableDefinitions)
{
AST nodeForDefiningGlobalVariables = ast.getChild(0).getChild(0);
if (variableDefinitions == null)
{
return;
}
foreach (VariableDefinition vd in variableDefinitions)
{
Token token = new Token(Token.TokenType.VAR_DECLARATION, "<VAR_DECL>", ast.getToken().LineNr, ast.getToken().LinePosition);
AST_VariableDeclaration declarationTree =
new AST_VariableDeclaration(token,
ReturnValueConversions.SystemTypeToReturnValueType(vd.initValue.GetType()),
vd.variableName);
if (vd.initValue != null)
{
AST assignmentTree = CreateAssignmentTreeFromInitValue(vd.variableName, vd.initValue);
AST declarationAndAssignmentTree = new AST(new Token(Token.TokenType.STATEMENT_LIST, "<DECLARATION_AND_ASSIGNMENT>", declarationTree.getToken().LineNr, declarationTree.getToken().LinePosition));
declarationAndAssignmentTree.addChild(declarationTree);
declarationAndAssignmentTree.addChild(assignmentTree);
nodeForDefiningGlobalVariables.addChild(declarationAndAssignmentTree);
}
else
{
nodeForDefiningGlobalVariables.addChild(declarationTree);
}
}
}
public void ChangeGlobalVariableInitValue(string pName, object pobject)
{
bool foundVariable = false;
AST statementListTree = m_ast.getChild(0);
AST globalVarDefs = statementListTree.getChild(0);
if (globalVarDefs.getTokenString() != "<GLOBAL_VARIABLE_DEFINITIONS_LIST>")
{
throw new Exception("Wrong node, " + globalVarDefs.getTokenString());
}
if (globalVarDefs.getChildren() != null && globalVarDefs.getChildren().Count > 0)
{
foreach (AST defAndAssignmentNode in globalVarDefs.getChildren())
{
AST_Assignment assigmentNode = (AST_Assignment)defAndAssignmentNode.getChild(1);
if (assigmentNode.VariableName == pName)
{
defAndAssignmentNode.removeChild(1);
defAndAssignmentNode.addChild(CreateAssignmentTreeFromInitValue(pName, pobject));
foundVariable = true;
break;
}
}
}
if (!foundVariable)
{
throw new Exception("Couldn't find and change the variable " + pName);
}
}
private void evaluateIfScope(AST tree)
{
Scope subscope = new Scope(Scope.ScopeType.IF_SCOPE, "<IF-SUBSCOPE>", m_currentScope);
m_currentScope = subscope;
AST_IfNode ifNode = (tree as AST_IfNode);
Debug.Assert(ifNode != null);
#if WRITE_DEBUG_INFO
Console.WriteLine("\nDefined IF-subscope for ifNode at line " + ifNode.getToken().LineNr);
#endif
ifNode.setScope(subscope); // save the new scope in the IF-token tree node
// Evaluate expression
evaluateScopeDeclarationsInAllChildren(tree.getChild(0));
AST trueNode = ifNode.getChild(1);
AST falseNode = null;
if (ifNode.getChildren().Count == 3)
{
falseNode = ifNode.getChild(2);
}
evaluateScopeDeclarationsInAllChildren(trueNode);
if (falseNode != null)
{
evaluateScopeDeclarationsInAllChildren(falseNode);
}
m_currentScope = m_currentScope.getEnclosingScope(); // pop scope
}
private void varDeclaration(AST tree)
{
string typeName = tree.getChild(0).getTokenString();
ReturnValueType variableType = ReturnValue.getReturnValueTypeFromString(typeName);
string variableName = tree.getChild(1).getTokenString();
switch (variableType)
{
case ReturnValueType.FLOAT:
m_currentMemorySpace.setValue(variableName, new ReturnValue(0.0f));
break;
case ReturnValueType.STRING:
m_currentMemorySpace.setValue(variableName, new ReturnValue(0.0f));
break;
default:
throw new InvalidOperationException("Can't declare a variable of type " + typeName);
}
}
private void evaluateFunctionScope(AST tree)
{
// Define function name
ReturnValueType returnType = ReturnValue.getReturnValueTypeFromString(tree.getChild(0).getTokenString());
string functionName = tree.getChild(1).getTokenString();
Symbol functionScope = new FunctionSymbol(m_currentScope, functionName, returnType, tree);
m_globalScope.define(functionScope); // all functions are saved in the global scope
m_currentScope = (Scope)functionScope;
AST_FunctionDefinitionNode functionCallNode = (AST_FunctionDefinitionNode)(tree);
functionCallNode.setScope((Scope)functionScope);
#if WRITE_DEBUG_INFO
Console.WriteLine("\nDefined function with name " + functionName + " and return type " + returnType);
#endif
// Process the body of the function
evaluateScopeDeclarations(tree.getChild(3));
m_currentScope = m_currentScope.getEnclosingScope(); // pop scope
}
private void addToList(List <AST> list, AST ast)
{
switch (ast.getTokenType())
{
case Token.TokenType.FUNC_DECLARATION:
addToList(list, ast.getChild(2));
addToList(list, ast.getChild(3));
break;
case Token.TokenType.IF:
addToList(list, ast.getChild(0));
list.Add(ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
break;
case Token.TokenType.LOOP:
list.Add(ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
break;
case Token.TokenType.LOOP_BLOCK:
list.Add(ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
break;
default:
addChildren(list, ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
list.Add(ast);
break;
}
}
private void evaluateReferencesForFUNCTION_CALL(AST tree)
{
// Function name:
string functionName = tree.getTokenString();
var sym = m_currentScope.resolve(functionName);
FunctionSymbol function = sym as FunctionSymbol;
if (function == null)
{
m_errorHandler.errorOccured("Can't find function with name " + functionName,
Error.ErrorType.SCOPE,
tree.getToken().LineNr,
tree.getToken().LinePosition
);
}
else
{
#if WRITE_DEBUG_INFO
Console.WriteLine("Resolved function call with name " + functionName + " (on line " + tree.getToken().LineNr + ")");
#endif
// Parameters
evaluateReferencesInAllChildren(tree);
AST node = function.getFunctionDefinitionNode();
AST_FunctionDefinitionNode functionDefinitionTree = (AST_FunctionDefinitionNode)(node);
/*if(functionDefinitionTree.getTokenString() != "<EXTERNAL_FUNC_DECLARATION>") {
* evaluateReferencesForFUNC_DECLARATION(functionDefinitionTree);
* }*/
// Setup reference to Function Definition AST node
AST_FunctionCall functionCallAst = tree as AST_FunctionCall;
Debug.Assert(functionCallAst != null);
functionCallAst.FunctionDefinitionRef = functionDefinitionTree;
List <AST> calleeParameterList = functionDefinitionTree.getChild(2).getChildren();
// Check that the number of arguments is right
AST callerParameterList = tree.getChild(0);
List <AST> arguments = callerParameterList.getChildren();
if (arguments.Count != calleeParameterList.Count)
{
m_errorHandler.errorOccured(
"Wrong nr of arguments to '" + functionDefinitionTree.getChild(1).getTokenString() + "' , expected " + calleeParameterList.Count + " but got " + arguments.Count
, Error.ErrorType.SYNTAX, tree.getToken().LineNr, tree.getToken().LinePosition);
}
}
}
private void evaluateFunctionScope(AST tree)
{
// Define function name
ReturnValueType returnType = ReturnValue.getReturnValueTypeFromString(tree.getChild(0).getTokenString());
string functionName = tree.getChild(1).getTokenString();
Symbol functionScope = new FunctionSymbol(m_currentScope, functionName, returnType, tree);
m_globalScope.define(functionScope); // all functions are saved in the global scope
m_currentScope = (Scope)functionScope;
AST_FunctionDefinitionNode functionCallNode = (AST_FunctionDefinitionNode)(tree);
functionCallNode.setScope((Scope)functionScope);
#if WRITE_DEBUG_INFO
Console.WriteLine("\nDefined function with name " + functionName + " and return type " + returnType);
#endif
// Process the body of the function
evaluateScopeDeclarations(tree.getChild(3));
m_currentScope = m_currentScope.getEnclosingScope(); // pop scope
}
public void BasicEvaluation()
{
Tokenizer tokenizer = new Tokenizer(s_errorHandler, true);
List <Token> tokens = tokenizer.process(File.OpenText("code9.txt"));
Parser parser = new Parser(tokens, s_errorHandler);
parser.process();
AST root = parser.getAST();
AST expressionTree = root.getChild(0).getChild(0);
ExpressionEvaluator e1 = new ExpressionEvaluator(expressionTree);
Assert.AreEqual(26, e1.getValue());
}
public void HandleNegativeNumbers()
{
Tokenizer tokenizer = new Tokenizer(s_errorHandler, true);
List <Token> tokens = tokenizer.process(File.OpenText("code10.txt"));
Parser parser = new Parser(tokens, s_errorHandler);
parser.process();
AST root = parser.getAST();
AST expressionTree = root.getChild(0).getChild(0);
ExpressionEvaluator e = new ExpressionEvaluator(expressionTree);
Assert.AreEqual(-5, e.getValue());
}
private void returnStatement(AST tree)
{
ReturnValue returnValue = new ReturnValue();
if (tree.getChildren().Count > 0)
{
returnValue = execute(tree.getChild(0));
}
if (returnValue != null)
{
#if WRITE_DEBUG_INFO
Console.Write("Return value was: ");
printReturnValue(returnValue);
#endif
throw returnValue;
}
}
private ExternalFunctionCreator AddExternalFunctions(FunctionDefinition[] functionDefinitions, AST ast)
{
List <FunctionDefinition> allFunctionDefinitions = new List <FunctionDefinition>();
allFunctionDefinitions.AddRange(builtInFunctions);
allFunctionDefinitions.AddRange(functionDefinitions);
ExternalFunctionCreator externalFunctionCreator = new ExternalFunctionCreator(allFunctionDefinitions.ToArray());
AST functionList = ast.getChild(1);
foreach (AST externalFunction in externalFunctionCreator.FunctionASTs)
{
functionList.addChild(externalFunction);
}
return(externalFunctionCreator);
}
private void evaluateIfScope(AST tree)
{
Scope subscope = new Scope(Scope.ScopeType.IF_SCOPE,"<IF-SUBSCOPE>", m_currentScope);
#if WRITE_DEBUG_INFO
Console.WriteLine("\nDefined IF-subscope");
#endif
m_currentScope = subscope;
AST_IfNode ifNode = (tree as AST_IfNode);
Debug.Assert(ifNode != null);
ifNode.setScope(subscope); // save the new scope in the IF-token tree node
// Evaluate expression
evaluateScopeDeclarationsInAllChildren(tree.getChild(0));
AST trueNode = ifNode.getChild(1);
AST falseNode = null;
if (ifNode.getChildren().Count == 3)
{
falseNode = ifNode.getChild(2);
}
evaluateScopeDeclarationsInAllChildren(trueNode);
if (falseNode != null)
{
evaluateScopeDeclarationsInAllChildren(falseNode);
}
m_currentScope = m_currentScope.getEnclosingScope(); // pop scope
}
private ReturnValue function(AST tree, List <ReturnValue> parameterValues)
{
// Push scope
Scope m_previousScope = m_currentScope;
AST_FunctionDefinitionNode functionDefinitionNode = (AST_FunctionDefinitionNode)(tree);
Assert.IsNotNull(functionDefinitionNode);
m_currentScope = (Scope)functionDefinitionNode.getScope();
Assert.IsNotNull(m_currentScope);
// Push memory space
MemorySpace m_previousMemorySpace = m_currentMemorySpace;
MemorySpace functionMemorySpace =
new MemorySpace("<FUNCTION_SPACE " + tree.getChild(1).getTokenString() + ">");
m_memoryStack.Push(functionMemorySpace);
m_currentMemorySpace = functionMemorySpace;
// Add parameters to memory space
List <AST> parameterDeclarations = tree.getChild(2).getChildren();
if (parameterDeclarations != null)
{
if (parameterDeclarations.Count != parameterValues.Count)
{
m_errorHandler.errorOccured(
"The number of arguments in function " +
tree.getChild(1).getTokenString() +
" does not match!",
Error.ErrorType.SYNTAX);
}
foreach (AST parameter in parameterDeclarations)
{
varDeclaration(parameter);
}
}
// Assign values to parameters
if (parameterValues != null)
{
int i = 0;
foreach (ReturnValue parameterValue in parameterValues)
{
string parameterName = parameterDeclarations[i].getChild(1).getTokenString();
assignValue(parameterName, parameterValue);
i++;
}
}
// Execute function
ReturnValue returnValue = null;
try {
executeAllChildNodes(tree.getChild(3)); // child 3 is the function body
}
catch (ReturnValue functionReturnValue) {
returnValue = functionReturnValue;
}
// Pop memory space
m_memoryStack.Pop();
m_currentMemorySpace = m_previousMemorySpace;
// Pop scope
m_currentScope = m_previousScope;
Assert.IsNotNull(m_currentScope);
return(returnValue);
}
private ReturnValue operation(AST tree)
{
ReturnValue returnValue = null;
float lhs = execute(tree.getChild(0)).FloatValue;
float rhs = execute(tree.getChild(1)).FloatValue;
if (tree.getTokenString() == "+")
{
returnValue = new ReturnValue(lhs + rhs);
}
else if (tree.getTokenString() == "-")
{
returnValue = new ReturnValue(lhs - rhs);
}
else if (tree.getTokenString() == "*")
{
returnValue = new ReturnValue(lhs * rhs);
}
else if (tree.getTokenString() == "/")
{
returnValue = new ReturnValue(lhs / rhs);
}
else if (tree.getTokenString() == "<")
{
float v = lhs < rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if (tree.getTokenString() == ">")
{
float v = lhs > rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if (tree.getTokenString() == "<=")
{
float v = lhs <= rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if (tree.getTokenString() == ">=")
{
float v = lhs >= rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if (tree.getTokenString() == "==")
{
float v = lhs == rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if (tree.getTokenString() == "!=")
{
float v = lhs != rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if (tree.getTokenString() == "&&")
{
float v = ((lhs != 0 ? true : false) && (rhs != 0 ? true : false)) ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if (tree.getTokenString() == "||")
{
float v = ((lhs != 0 ? true : false) || (rhs != 0 ? true : false)) ? 1 : 0;
returnValue = new ReturnValue(v);
}
else
{
throw new NotImplementedException("Operator " + tree.getTokenString() + " isn't implemented yet!");
}
return(returnValue);
}
private ReturnValue function(AST tree, List<ReturnValue> parameterValues)
{
// Push scope
Scope m_previousScope = m_currentScope;
AST_FunctionDefinitionNode functionDefinitionNode = (AST_FunctionDefinitionNode)(tree);
Assert.IsNotNull(functionDefinitionNode);
m_currentScope = (Scope)functionDefinitionNode.getScope();
Assert.IsNotNull(m_currentScope);
// Push memory space
MemorySpace m_previousMemorySpace = m_currentMemorySpace;
MemorySpace functionMemorySpace =
new MemorySpace("<FUNCTION_SPACE " + tree.getChild(1).getTokenString() + ">");
m_memoryStack.Push(functionMemorySpace);
m_currentMemorySpace = functionMemorySpace;
// Add parameters to memory space
List<AST> parameterDeclarations = tree.getChild(2).getChildren();
if(parameterDeclarations != null) {
if(parameterDeclarations.Count != parameterValues.Count) {
m_errorHandler.errorOccured(
"The number of arguments in function " +
tree.getChild(1).getTokenString() +
" does not match!",
Error.ErrorType.SYNTAX);
}
foreach(AST parameter in parameterDeclarations) {
varDeclaration(parameter);
}
}
// Assign values to parameters
if(parameterValues != null) {
int i = 0;
foreach(ReturnValue parameterValue in parameterValues) {
string parameterName = parameterDeclarations[i].getChild(1).getTokenString();
assignValue(parameterName, parameterValue);
i++;
}
}
// Execute function
ReturnValue returnValue = null;
try {
executeAllChildNodes(tree.getChild(3)); // child 3 is the function body
}
catch(ReturnValue functionReturnValue) {
returnValue = functionReturnValue;
}
// Pop memory space
m_memoryStack.Pop();
m_currentMemorySpace = m_previousMemorySpace;
// Pop scope
m_currentScope = m_previousScope;
Assert.IsNotNull(m_currentScope);
return returnValue;
}
private void returnStatement(AST tree)
{
ReturnValue returnValue = new ReturnValue();
if (tree.getChildren().Count > 0)
{
returnValue = execute(tree.getChild(0));
}
if(returnValue != null) {
#if WRITE_DEBUG_INFO
Console.Write("Return value was: ");
printReturnValue(returnValue);
#endif
throw returnValue;
}
}
private void addToList(List<AST> list, AST ast)
{
switch (ast.getTokenType())
{
case Token.TokenType.FUNC_DECLARATION:
addToList(list, ast.getChild(2));
addToList(list, ast.getChild(3));
break;
case Token.TokenType.IF:
addToList(list, ast.getChild(0));
list.Add(ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
break;
case Token.TokenType.LOOP:
list.Add(ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
break;
case Token.TokenType.LOOP_BLOCK:
list.Add(ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
break;
default:
addChildren(list, ast);
#if WRITE_DEBUG_INFO
Console.WriteLine(": " + ast.getTokenString() + " of type " + ast.getTokenType());
#endif
list.Add(ast);
break;
}
}
private float evaluate(AST tree)
{
float returnValue = 0;
if(tree.getTokenType() == Token.TokenType.NUMBER) {
returnValue = (float)System.Convert.ToDouble(tree.getTokenString());
}
else if(tree.getTokenType() == Token.TokenType.OPERATOR) {
if(tree.getTokenString() == "+") {
returnValue = evaluate(tree.getChild(0)) + evaluate(tree.getChild(1));
}
else if(tree.getTokenString() == "-") {
returnValue = evaluate(tree.getChild(0)) - evaluate(tree.getChild(1));
}
else if(tree.getTokenString() == "*") {
returnValue = evaluate(tree.getChild(0)) * evaluate(tree.getChild(1));
}
else if(tree.getTokenString() == "/") {
returnValue = evaluate(tree.getChild(0)) / evaluate(tree.getChild(1));
}
else if(tree.getTokenString() == "<") {
returnValue = (evaluate(tree.getChild(0)) < evaluate(tree.getChild(1))) ? 1 : 0;
}
else if(tree.getTokenString() == ">") {
returnValue = (evaluate(tree.getChild(0)) > evaluate(tree.getChild(1))) ? 1 : 0;
}
else if(tree.getTokenString() == "<=") {
returnValue = (evaluate(tree.getChild(0)) <= evaluate(tree.getChild(1))) ? 1 : 0;
}
else if(tree.getTokenString() == ">=") {
returnValue = (evaluate(tree.getChild(0)) >= evaluate(tree.getChild(1))) ? 1 : 0;
}
else if(tree.getTokenString() == "&&") {
returnValue = (evaluate(tree.getChild(0)) != 0 && evaluate(tree.getChild(1)) != 0) ? 1 : 0;
}
else if(tree.getTokenString() == "||") {
returnValue = (evaluate(tree.getChild(0)) != 0 || evaluate(tree.getChild(1)) != 0) ? 1 : 0;
}
else if(tree.getTokenString() == "!=") {
returnValue = (evaluate(tree.getChild(0)) != evaluate(tree.getChild(1))) ? 1 : 0;
}
else if(tree.getTokenString() == "==") {
returnValue = (evaluate(tree.getChild(0)) == evaluate(tree.getChild(1))) ? 1 : 0;
}
else {
throw new InvalidOperationException("ExpressionEvaluator can't handle operators with string " + tree.getTokenString());
}
}
else {
throw new InvalidOperationException("ExpressionEvaluator can't handle tokens of type " + tree.getTokenType());
}
return returnValue;
}
private ReturnValue operation(AST tree)
{
ReturnValue returnValue = null;
float lhs = execute(tree.getChild(0)).FloatValue;
float rhs = execute(tree.getChild(1)).FloatValue;
if(tree.getTokenString() == "+") {
returnValue = new ReturnValue(lhs + rhs);
}
else if(tree.getTokenString() == "-") {
returnValue = new ReturnValue(lhs - rhs);
}
else if(tree.getTokenString() == "*") {
returnValue = new ReturnValue(lhs * rhs);
}
else if(tree.getTokenString() == "/") {
returnValue = new ReturnValue(lhs / rhs);
}
else if(tree.getTokenString() == "<") {
float v = lhs < rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if(tree.getTokenString() == ">") {
float v = lhs > rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if(tree.getTokenString() == "<=") {
float v = lhs <= rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if(tree.getTokenString() == ">=") {
float v = lhs >= rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if(tree.getTokenString() == "==") {
float v = lhs == rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if(tree.getTokenString() == "!=") {
float v = lhs != rhs ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if(tree.getTokenString() == "&&") {
float v = ((lhs != 0 ? true : false) && (rhs != 0 ? true : false)) ? 1 : 0;
returnValue = new ReturnValue(v);
}
else if(tree.getTokenString() == "||") {
float v = ((lhs != 0 ? true : false) || (rhs != 0 ? true : false)) ? 1 : 0;
returnValue = new ReturnValue(v);
}
else {
throw new NotImplementedException("Operator " + tree.getTokenString() + " isn't implemented yet!");
}
return returnValue;
}
private float evaluate(AST tree)
{
float returnValue = 0;
if (tree.getTokenType() == Token.TokenType.NUMBER)
{
returnValue = (float)System.Convert.ToDouble(tree.getTokenString());
}
else if (tree.getTokenType() == Token.TokenType.OPERATOR)
{
if (tree.getTokenString() == "+")
{
returnValue = evaluate(tree.getChild(0)) + evaluate(tree.getChild(1));
}
else if (tree.getTokenString() == "-")
{
returnValue = evaluate(tree.getChild(0)) - evaluate(tree.getChild(1));
}
else if (tree.getTokenString() == "*")
{
returnValue = evaluate(tree.getChild(0)) * evaluate(tree.getChild(1));
}
else if (tree.getTokenString() == "/")
{
returnValue = evaluate(tree.getChild(0)) / evaluate(tree.getChild(1));
}
else if (tree.getTokenString() == "<")
{
returnValue = (evaluate(tree.getChild(0)) < evaluate(tree.getChild(1))) ? 1 : 0;
}
else if (tree.getTokenString() == ">")
{
returnValue = (evaluate(tree.getChild(0)) > evaluate(tree.getChild(1))) ? 1 : 0;
}
else if (tree.getTokenString() == "<=")
{
returnValue = (evaluate(tree.getChild(0)) <= evaluate(tree.getChild(1))) ? 1 : 0;
}
else if (tree.getTokenString() == ">=")
{
returnValue = (evaluate(tree.getChild(0)) >= evaluate(tree.getChild(1))) ? 1 : 0;
}
else if (tree.getTokenString() == "&&")
{
returnValue = (evaluate(tree.getChild(0)) != 0 && evaluate(tree.getChild(1)) != 0) ? 1 : 0;
}
else if (tree.getTokenString() == "||")
{
returnValue = (evaluate(tree.getChild(0)) != 0 || evaluate(tree.getChild(1)) != 0) ? 1 : 0;
}
else if (tree.getTokenString() == "!=")
{
returnValue = (evaluate(tree.getChild(0)) != evaluate(tree.getChild(1))) ? 1 : 0;
}
else if (tree.getTokenString() == "==")
{
returnValue = (evaluate(tree.getChild(0)) == evaluate(tree.getChild(1))) ? 1 : 0;
}
else
{
throw new InvalidOperationException("ExpressionEvaluator can't handle operators with string " + tree.getTokenString());
}
}
else
{
throw new InvalidOperationException("ExpressionEvaluator can't handle tokens of type " + tree.getTokenType());
}
return(returnValue);
}
private ExternalFunctionCreator AddExternalFunctions(FunctionDefinition[] functionDefinitions, AST ast)
{
List<FunctionDefinition> allFunctionDefinitions = new List<FunctionDefinition>();
allFunctionDefinitions.AddRange(builtInFunctions);
allFunctionDefinitions.AddRange(functionDefinitions);
// HasFunction requires a reference to the SprakRunner
FunctionDocumentation functionDoc_HasFunction =
new FunctionDocumentation("Check if a function exists on the object", new string[] { "The name of the function" });
allFunctionDefinitions.Add(new FunctionDefinition("bool", "HasFunction", new string[] { "string" }, new string[] { "functionName" }, new ExternalFunctionCreator.OnFunctionCall(API_hasFunction), functionDoc_HasFunction));
ExternalFunctionCreator externalFunctionCreator = new ExternalFunctionCreator(allFunctionDefinitions.ToArray());
AST functionList = ast.getChild(1);
foreach (AST externalFunction in externalFunctionCreator.FunctionASTs)
{
functionList.addChild(externalFunction);
}
return externalFunctionCreator;
}
private void evaluateReferencesForFUNC_DECLARATION(AST tree)
{
string functionName = tree.getChild(1).getTokenString();
m_currentScope = (Scope)m_currentScope.resolve(functionName); // push the scope with the function
#if WRITE_DEBUG_INFO
Console.WriteLine("\n Trying to resolve function parameters and body of " + functionName);
#endif
evaluateReferencesInAllChildren(tree.getChild(2)); // parameters
evaluateReferencesInAllChildren(tree.getChild(3)); // function body
m_currentScope = m_currentScope.getEnclosingScope(); // pop scope
}
private ExternalFunctionCreator AddExternalFunctions(FunctionDefinition[] functionDefinitions, AST ast)
{
List<FunctionDefinition> allFunctionDefinitions = new List<FunctionDefinition>();
allFunctionDefinitions.AddRange(builtInFunctions);
allFunctionDefinitions.AddRange(functionDefinitions);
ExternalFunctionCreator externalFunctionCreator = new ExternalFunctionCreator(allFunctionDefinitions.ToArray());
AST functionList = ast.getChild(1);
foreach (AST externalFunction in externalFunctionCreator.FunctionASTs)
{
functionList.addChild(externalFunction);
}
return externalFunctionCreator;
}
void AddLocalVariables(AST ast, VariableDefinition[] variableDefinitions)
{
AST nodeForDefiningGlobalVariables = ast.getChild(0).getChild(0);
if(variableDefinitions == null) { return; }
foreach(VariableDefinition vd in variableDefinitions) {
Token token = new Token(Token.TokenType.VAR_DECLARATION,"<VAR_DECL>", ast.getToken().LineNr, ast.getToken().LinePosition);
AST_VariableDeclaration declarationTree =
new AST_VariableDeclaration(token,
vd.initValue.getReturnValueType(),
vd.variableName);
if(vd.initValue != null)
{
AST assignmentTree = CreateAssignmentTreeFromInitValue(vd.variableName, vd.initValue);
AST declarationAndAssignmentTree = new AST(new Token(Token.TokenType.STATEMENT_LIST, "<DECLARATION_AND_ASSIGNMENT>", declarationTree.getToken().LineNr, declarationTree.getToken().LinePosition));
declarationAndAssignmentTree.addChild(declarationTree);
declarationAndAssignmentTree.addChild(assignmentTree);
nodeForDefiningGlobalVariables.addChild(declarationAndAssignmentTree);
}
else
{
nodeForDefiningGlobalVariables.addChild(declarationTree);
}
}
}
private void ifThenElse(AST tree)
{
// Push scope
AST_IfNode ifNode = (AST_IfNode)(tree);
Assert.IsNotNull(ifNode);
m_currentScope = (Scope)ifNode.getScope();
Assert.IsNotNull(m_currentScope);
// Evaluate conditional
ReturnValue conditionalExpression = execute(tree.getChild(0));
if (conditionalExpression.FloatValue != 0) {
Assert.IsNotNull(tree.getChild(1));
execute(tree.getChild(1));
}
else {
if (tree.getChildren().Count == 3) {
Assert.IsNotNull(tree.getChild(2));
execute(tree.getChild(2));
}
}
// Pop scope
m_currentScope = (Scope)ifNode.getScope().getEnclosingScope();
Assert.IsNotNull(m_currentScope);
}
private void evaluateReferencesForFUNCTION_CALL(AST tree)
{
// Function name:
string functionName = tree.getTokenString();
FunctionSymbol function = (FunctionSymbol)m_currentScope.resolve(functionName);
if (function == null)
{
m_errorHandler.errorOccured("Can't find function with name " + functionName,
Error.ErrorType.SCOPE,
tree.getToken().LineNr,
tree.getToken().LinePosition
);
}
else
{
#if WRITE_DEBUG_INFO
Console.WriteLine("Resolved function call with name " + functionName + " (on line " + tree.getToken().LineNr + ")");
#endif
// Parameters
evaluateReferencesInAllChildren(tree);
AST node = function.getFunctionDefinitionNode();
AST_FunctionDefinitionNode functionDefinitionTree = (AST_FunctionDefinitionNode)(node);
/*if(functionDefinitionTree.getTokenString() != "<EXTERNAL_FUNC_DECLARATION>") {
evaluateReferencesForFUNC_DECLARATION(functionDefinitionTree);
}*/
// Setup reference to Function Definition AST node
AST_FunctionCall functionCallAst = tree as AST_FunctionCall;
Debug.Assert(functionCallAst != null);
functionCallAst.FunctionDefinitionRef = functionDefinitionTree;
List<AST> calleeParameterList = functionDefinitionTree.getChild(2).getChildren();
// Check that the number of arguments is right
AST callerParameterList = tree.getChild(0);
List<AST> arguments = callerParameterList.getChildren();
if (arguments.Count != calleeParameterList.Count)
{
m_errorHandler.errorOccured(
"Wrong number of arguments to function"
, Error.ErrorType.SYNTAX, tree.getToken().LineNr, tree.getToken().LinePosition);
}
}
}
private void varDeclaration(AST tree)
{
string typeName = tree.getChild(0).getTokenString();
ReturnValueType variableType = ReturnValue.getReturnValueTypeFromString(typeName);
string variableName = tree.getChild(1).getTokenString();
switch(variableType) {
case ReturnValueType.FLOAT:
m_currentMemorySpace.setValue(variableName, new ReturnValue(0.0f));
break;
case ReturnValueType.STRING:
m_currentMemorySpace.setValue(variableName, new ReturnValue(0.0f));
break;
default:
throw new InvalidOperationException("Can't declare a variable of type " + typeName);
}
}