public void visitVarDeclaration(VarDeclarationNode node)
{
IdentifierNode identifier = (IdentifierNode)node.getChildren()[0];
string variableName = identifier.getVariableName();
if (this.forLoopControlVariables.Count > 0)
{
throw new SemanticException("Declaring variables inside for loop is not allowed.");
}
if (variableAlreadyDeclared(variableName))
{
throw new SemanticException("Variable '" + variableName + "' already declared.");
}
TypeNode typeNode = (TypeNode)node.getChildren()[1];
MiniPLTokenType type = (MiniPLTokenType)typeNode.getValue();
if (type == MiniPLTokenType.TYPE_IDENTIFIER_INTEGER)
{
this.symbolTable.addVariable(variableName, 0);
}
else if (type == MiniPLTokenType.TYPE_IDENTIFIER_STRING)
{
this.symbolTable.addVariable(variableName, "");
}
else if (type == MiniPLTokenType.TYPE_IDENTIFIER_BOOL)
{
this.symbolTable.addVariable(variableName, false);
}
else
{
throw new Exception("Unknown type usage in semantic analyzer.");
}
}
private void updateValue(INode node)
{
IdentifierNode identifier = (IdentifierNode)node.getChildren()[0];
string variableName = identifier.getVariableName();
INode possibleNode = node.getChildren()[1];
foreach (INode child in possibleNode.getChildren())
{
child.accept(this);
}
if (this.symbolTable.hasInteger(variableName))
{
this.symbolTable.updateVariable(variableName, popInt());
this.intType = false;
}
else if (this.symbolTable.hasString(variableName))
{
this.symbolTable.updateVariable(variableName, popString());
this.strType = false;
}
else if (this.symbolTable.hasBool(variableName))
{
this.symbolTable.updateVariable(variableName, popBool());
}
}
public void visitVarDeclaration(VarDeclarationNode node)
{
IdentifierNode identifier = (IdentifierNode)node.getChildren()[0];
string variableName = identifier.getVariableName();
TypeNode typeNode = (TypeNode)node.getChildren()[1];
MiniPLTokenType type = (MiniPLTokenType)typeNode.getValue();
typeCheck(typeNode, type);
}
public void visitIdentifier(IdentifierNode node)
{
string variableName = node.getVariableName();
if (!this.symbolTable.hasVariable(variableName))
{
throw new SemanticException("Variable '" + variableName + "' has not been declared.");
}
}
public void visitRead(ReadNode readNode)
{
IdentifierNode identifier = (IdentifierNode)readNode.getChildren()[0];
string variableName = identifier.getVariableName();
if (!this.symbolTable.hasInteger(variableName) && !this.symbolTable.hasString(variableName))
{
throw new SemanticException("Wrong type in read statement. Trying to read input to variable " + variableName + ". Read statement can read only integers and strings.");
}
}
public void visitIdentifier(IdentifierNode node)
{
if (!this.symbolTable.hasVariable(node.getVariableName()))
{
throw new SemanticException("Variable has not been declared.");
}
else
{
if (this.symbolTable.hasInteger(node.getVariableName()))
{
this.typeStack.Push(MiniPLTokenType.TYPE_IDENTIFIER_INTEGER);
}
if (this.symbolTable.hasString(node.getVariableName()))
{
this.typeStack.Push(MiniPLTokenType.TYPE_IDENTIFIER_STRING);
}
if (this.symbolTable.hasBool(node.getVariableName()))
{
this.typeStack.Push(MiniPLTokenType.TYPE_IDENTIFIER_BOOL);
}
}
}
public void visitForLoop(ForLoopNode node)
{
IdentifierNode identifier = (IdentifierNode)node.getChildren()[0];
string variableName = identifier.getVariableName();
if (!variableAlreadyDeclared(variableName))
{
throw new SemanticException("The control variable '" + variableName + "' in for loop has not been declared.");
}
this.forLoopControlVariables.Push(variableName);
node.getChildren()[2].accept(this);
this.forLoopControlVariables.Pop();
}
public void visitRead(ReadNode node)
{
IdentifierNode identifier = (IdentifierNode)node.getChildren()[0];
string variableName = identifier.getVariableName();
if (this.symbolTable.hasInteger(variableName))
{
this.symbolTable.updateVariable(variableName, readInteger());
}
else if (this.symbolTable.hasString(variableName))
{
this.symbolTable.updateVariable(variableName, readString());
}
}
public void visitVarAssignment(VarAssignmentNode node)
{
IdentifierNode identifier = (IdentifierNode)node.getChildren()[0];
string variableName = identifier.getVariableName();
if (!variableAlreadyDeclared(variableName))
{
throw new SemanticException("Variable '" + variableName + "' has not been declared.");
}
if (this.forLoopControlVariables.Contains(variableName))
{
throw new SemanticException("Control variable '" + variableName + "' cannot be assigned a new value inside for loop.");
}
}
public void visitIdentifier(IdentifierNode node)
{
string variableName = node.getVariableName();
if (this.symbolTable.hasInteger(variableName))
{
this.intType = true;
this.intStack.Push(this.symbolTable.getInt(variableName));
}
else if (this.symbolTable.hasString(variableName))
{
this.strType = true;
this.strStack.Push(this.symbolTable.getString(variableName));
}
else if (this.symbolTable.hasBool(variableName))
{
this.boolStack.Push(this.symbolTable.getBool(variableName));
}
}
public void visitForLoop(ForLoopNode forLoopNode)
{
IdentifierNode identifier = (IdentifierNode)forLoopNode.getChildren()[0];
string controlVariable = identifier.getVariableName();
RangeOperatorNode rangeNode = (RangeOperatorNode)forLoopNode.getChildren()[1];
StatementListNode forStatements = (StatementListNode)forLoopNode.getChildren()[2];
rangeNode.getChildren()[0].accept(this);
int begin = popInt();
rangeNode.getChildren()[1].accept(this);
int end = popInt();
for (int i = begin; i <= end; i++)
{
this.symbolTable.updateVariable(controlVariable, i);
foreach (INode child in forStatements.getChildren())
{
child.accept(this);
}
}
}
public void visitVarAssignment(VarAssignmentNode node)
{
IdentifierNode identifier = (IdentifierNode)node.getChildren()[0];
string variableName = identifier.getVariableName();
INode expression = node.getChildren()[1];
MiniPLTokenType type;
if (this.symbolTable.hasInteger(variableName))
{
type = MiniPLTokenType.TYPE_IDENTIFIER_INTEGER;
typeCheck(expression, type);
}
else if (this.symbolTable.hasString(variableName))
{
type = MiniPLTokenType.TYPE_IDENTIFIER_STRING;
typeCheck(expression, type);
}
else if (this.symbolTable.hasBool(variableName))
{
type = MiniPLTokenType.TYPE_IDENTIFIER_BOOL;
typeCheck(expression, type);
}
}