public LanguageIndexer(LanguageSettings languageSettings) { LanguageSettings = languageSettings; Exclusions = (from item in LanguageSettings.Tokens.Where(y => y.Type == TokenTypeOption.Stop) select item.Content).ToList(); HashSet <char> hs = new HashSet <char>(); if (LanguageSettings.Tokens.Any(y => y.Type.Equals(TokenTypeOption.Whitelist))) { foreach (var item in LanguageSettings.Tokens.Where(x => x.Type.Equals(TokenTypeOption.Whitelist))) { foreach (var c in item.Content.ToCharArray()) { if (hs.Add(c)) { Whitelist.Add(c); } } } } else { Whitelist.AddRange(Span(65, 90)); Whitelist.AddRange(Span(97, 122)); } }