public override SymbolDefinition AddDeclaration(SymbolDeclaration symbol)
    {
        symbol.scope = this;
        if (localSymbols == null)
        {
            localSymbols = new List <SymbolDefinition>();
        }

        var definition = SymbolDefinition.Create(symbol);

        localSymbols.Add(definition);

        return(definition);
    }