public void EnterSymbol(string symbolName, ASTnode astnode)
{
if (!IsDeclaredLocally(symbolName))
{
CurrentScope.Symbols.Add(symbolName, astnode);
}
else
{
throw new SemanticException($"Error on line {astnode.line}: Symbol {symbolName} already declared locally.");
}
}
public ASTnode RetrieveSymbol(string symbolName, ASTnode problemNode = null)
{
ASTnode returnValue;
Scope viewingScope = CurrentScope;
do
{
if (viewingScope.Symbols.TryGetValue(symbolName, out returnValue))
{
return(returnValue);
}
viewingScope = viewingScope.Parent;
}while (viewingScope != null);
if (problemNode != null)
{
throw new SemanticException($"Error on line {problemNode.line}: Symbol {symbolName} not found. Potentially missing declaration or not visible in scope.");
}
else
{
throw new SemanticException($"Symbol {symbolName} not found. Potentially missing declaration or not visible in scope.");
}
}
public void Visit(ASTnode ast)
{
ast.Accept(this);
}