public FormulaParser(string formula)
{
if (string.IsNullOrEmpty(formula))
{
throw new ArgumentNullException(nameof(formula));
}
expressionAccessor = new ExpressionAccessor(formula);
lexicalAnalyzer = new LexicalAnalyzer(expressionAccessor);
}
public LexicalAnalyzer(IExpressionAccessor expressionAccessor)
{
accessor = expressionAccessor
?? throw new ArgumentNullException(nameof(expressionAccessor));
}