// Declaration
public override TypeNode Visit(DeclarationNode node, object obj)
{
Symbol duplicate = SymbolTable.RetrieveSymbol(node.Id.Text);
// If declaration has assignment, get the type of the assignment
if (node.AssignmentExpression != null)
{
TypeNode assignmentType = Visit(node.AssignmentExpression, node.Type);
// If assignment type is not the same type as the declaration, log error
if (assignmentType != node.Type)
{
ErrorLogger.LogError(new IncompatibleTypesError(assignmentType, node.Type, node.AssignmentExpression.SourcePosition));
return(new ErrorTypeNode(node.SourcePosition));
}
}
// Enter in symbol table if not a duplicate, else log error
if (duplicate == null)
{
SymbolTable.EnterSymbol(node.Id.Text, node.Type);
}
else
{
ErrorLogger.LogError(new VariableAlreadyDeclaredError(node.Id.Text, node.Id.SourcePosition));
node.Type = new ErrorTypeNode(node.SourcePosition);
}
return(node.Type);
}
// Declaration
public override ASTNode VisitDclStmt(CLUBSParser.DclStmtContext context)
{
SourcePosition sourcePosition = new SourcePosition(context.start);
DeclarationNode node;
TypeNode type = GetTypeNode(context.type().kind.Type, sourcePosition);
IdentifierNode id = new IdentifierNode(context.id.Text, new SourcePosition(context.id));
// Check if declaration is a set.
if (context.set != null)
{
// If set, type should be wrapped in a set type.
node = new DeclarationNode(new SetTypeNode(type, sourcePosition), id, sourcePosition);
}
else
{
// Else, type should be as is.
node = new DeclarationNode(type, id, sourcePosition);
}
// Visit assignment if has any
if (context.assignment != null)
{
node.AssignmentExpression = Visit(context.assignment) as ExpressionNode;
}
return(node);
}
// Declaration
public override string Visit(DeclarationNode node, object obj)
{
StringBuilder builder = new StringBuilder();
// Append declaration of variable with a type-based default initialization
builder.Append($"{Visit(node.Type)} {node.Id} = {node.Type.GetInitializationString(node.Id.Text)}");
// If declaration has assignment, append new statement with assignment to the newly declared variable
if (node.AssignmentExpression != null)
{
builder.Append($"{node.Id} = {Visit(node.AssignmentExpression, node.Id)};\n");
}
SymbolTable.EnterSymbol(node.Id.Text, node.Type);
return(builder.ToString());
}
public abstract T Visit(DeclarationNode node, object obj);
