public void consumeCurrentToken()
{
Token nextToken;
if (m_nextTokenIndex < m_tokens.Count) {
nextToken = m_tokens[m_nextTokenIndex];
m_nextTokenIndex++;
}
else {
nextToken = new Token(Token.TokenType.EOF, "<EOF>");
}
m_lookahead[m_lookaheadIndex] = nextToken;
m_lookaheadIndex = (m_lookaheadIndex + 1) % k;
}
public void backtrackToToken(Token pToken)
{
m_nextTokenIndex = 0;
m_lookaheadIndex = 0;
for (int i = 0; i < k; i++) {
consumeCurrentToken();
}
while (lookAhead(1) != pToken) {
consumeCurrentToken ();
}
Console.WriteLine ("Found token");
}
public AST(Token token)
{
m_token = token;
nrOfASTsInMemory++;
}
public AST_FunctionCall(Token token)
: base(token)
{
}
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);
}
}
}
public AST_LoopBlockNode(Token token)
: base(token)
{
}
public AST_IfNode(Token token )
: base(token)
{
}
public AST(Token token)
{
m_token = token;
}
public AST_ArrayEndSignal(Token token)
: base(token)
{
}
void checkRightHandSide(AST rhs, Token operatorToken)
{
if(rhs == null) {
throw new Error("No expression on the right side of '" + operatorToken.getTokenString() + "'",
Error.ErrorType.SYNTAX, operatorToken.LineNr, operatorToken.LinePosition + 2);
}
}
void checkLeftHandSide(AST lhs, Token operatorToken)
{
if(lhs == null) {
throw new Error("No expression on the left side of '" + operatorToken.getTokenString() + "'",
Error.ErrorType.SYNTAX, operatorToken.LineNr, operatorToken.LinePosition - 1);
}
}
private AST assignmentToArray()
{
#if WRITE_DEBUG_INFO
Console.WriteLine("assignment to array");
#endif
Token nameToken = null;
AST indexNode = null;
#if WRITE_DEBUG_INFO
Console.WriteLine("normal array");
#endif
nameToken = match(Token.TokenType.NAME);
match(Token.TokenType.BRACKET_LEFT);
indexNode = expression();
match(Token.TokenType.BRACKET_RIGHT);
if(lookAheadType(1) == Token.TokenType.NEW_LINE ||
lookAheadType(1) == Token.TokenType.EOF)
{
// it's a statement without assignment
return indexNode;
}
Token assignmentToken = match(Token.TokenType.ASSIGNMENT);
AST expressionTree = expression();
if(expressionTree != null) {
Token arrayAssignmentToken = new Token(Token.TokenType.ASSIGNMENT_TO_ARRAY, "=", assignmentToken.LineNr, assignmentToken.LinePosition);
AST_Assignment assignmentTree = new AST_Assignment(arrayAssignmentToken, nameToken.getTokenString());
assignmentTree.addChild(indexNode);
assignmentTree.addChild(expressionTree);
/*ASTPainter p = new ASTPainter();
Console.WriteLine("---AST---");
p.PaintAST(assignmentTree);
Console.WriteLine("---------");*/
return assignmentTree;
}
else {
throw new Error("The expression after = makes no sense", Error.ErrorType.SYNTAX,
assignmentToken.LineNr, assignmentToken.LinePosition);
}
}
public virtual Token match(Token.TokenType expectedTokenType)
{
Token matchedToken = lookAhead(1);
if(lookAheadType(1) == expectedTokenType) {
#if WRITE_DEBUG_INFO
Console.WriteLine("MATCHED TOKEN " + lookAhead(1).getTokenString() + " (line " + lookAhead(1).LineNr + ")");
#endif
consumeCurrentToken();
} else {
#if WRITE_DEBUG_INFO
Console.WriteLine("FAILED TO MATCH TOKEN OF TYPE " + expectedTokenType.ToString() +
" ...FOUND " + lookAhead(1).getTokenString() + " (line " + lookAhead(1).LineNr + ")");
#endif
throw new Error(
"The code word '" + lookAhead(1).getTokenString() + "'" +
" does not compute. Expected " + expectedTokenType,
Error.ErrorType.SYNTAX,
lookAhead(1).LineNr,
lookAhead(1).LinePosition);
}
return matchedToken;
}
public AST_Assignment(Token token, string variableName)
: base(token)
{
m_variableName = variableName;
}
public AST_LoopNode(Token token )
: base(token)
{
}
public void addChild(Token token)
{
AST childTree = new AST(token);
addChild(childTree);
}
public AST_FunctionDefinitionNode(Token token)
: base(token)
{
}
public AST_VariableDeclaration(Token token, ReturnValueType type, string name)
: base(token)
{
m_type = type;
m_name = name;
}