public override void EnterVariableIndex([NotNull] FormulaParser.VariableIndexContext context)
{
resultBuilder.Append($"\"{context.GetText()}\"");
}
/// <summary>
/// Exit a parse tree produced by <see cref="FormulaParser.variableIndex"/>.
/// <para>The default implementation does nothing.</para>
/// </summary>
/// <param name="context">The parse tree.</param>
public virtual void ExitVariableIndex([NotNull] FormulaParser.VariableIndexContext context)
{
}