/// <summary>
/// Checks the static semantic constraints of a BinOpNode.
/// </summary>
///
/// <returns>An ISemanticCheckValue.</returns>
/// <param name="node">Node.</param>
public ISemanticCheckValue VisitDeclarationNode(DeclarationNode node)
{
// check that the id property is ok
IProperty property = getVariableProperty(node);
if (property == voidProperty)
{
return(voidProperty);
}
VariableIdNode idNode = node.IDNode;
// if the property is declared already, it's an error
if (property.Declared)
{
analyzer.notifyError(new DeclarationError(idNode));
}
else
{
// if it wasn't declared, now it is.
property.Declared = true;
// check the AssignNode
node.AssignNode.Accept(this);
}
return(voidProperty);
}
/// <summary>
/// Visits the declaration node.
/// </summary>
/// <returns>An ISemanticCheckValue.</returns>
/// <param name="node">Node.</param>
public ISemanticCheckValue VisitDeclarationNode(DeclarationNode node)
{
// adds the id into the symbolic table and executes the assign node
addNewId(node.IDNode);
node.AssignNode.Accept(this);
return(voidProperty);
}
public DeclarationNode CreateDeclarationNode(VariableIdNode idNode, StatementsNode statementsNode, Token t)
{
DeclarationNode declarationNode = new DeclarationNode(idNode, symbolTable, t);
declarationNode.AssignNode = CreateAssignNode(idNode, t);
statementsNode.Statement = declarationNode;
return(declarationNode);
}
/// <summary>
/// Parses a declaration statement.
/// </summary>
/// <returns>The next token.</returns>
/// <param name="token">Token.</param>
/// <param name="statementsNode">A StatementsNode.</param>
private Token ParseDeclaration(Token token, StatementsNode statementsNode)
{
// Try to parse all the pieces that a DeclarationNode needs to be evaluated.
try {
VariableIdNode idNode = nodeBuilder.CreateIdNode();
// parse the target id
Token next = ParseVarId(scanner.getNextToken(token), idNode);
match(next, TokenType.SET_TYPE);
// parse the id's type
next = ParseType(scanner.getNextToken(next), idNode);
// create the actual DeclarationNode
DeclarationNode declarationNode = nodeBuilder.CreateDeclarationNode(idNode, statementsNode, token);
// parse the assign for the DeclarationNode
return(ParseAssign(next, declarationNode.AssignNode));
} catch (UnexpectedTokenException ex) {
return(FastForwardToStatementEnd(ex));
}
}
/// <summary>
/// Visits the declaration node.
/// </summary>
/// <returns>An ISemanticCheckValue.</returns>
/// <param name="node">Node.</param>
public ISemanticCheckValue VisitDeclarationNode(DeclarationNode node)
{
// nothing to evaluate here, it's done from the ExecutionVisitor
return(voidProperty);
}
/// <summary>
/// Visits the declaration node.
/// </summary>
/// <returns>An ISemanticCheckValue.</returns>
/// <param name="node">Node.</param>
public ISemanticCheckValue VisitDeclarationNode(DeclarationNode node)
{
// return the evaluation of the node's assignment
return(node.AssignNode.Accept(this));
}