Boo.BooLangService.StringParsing.ExcludeStringMatcher.FindNextIndex C# (CSharp) Метод

        public int? FindNextIndex(char value)
        {
            var stringWalker = new StringWalker();
            var startingSource = source.Substring(startIndex);

            foreach (var position in stringWalker.Iterate(startingSource))
            {
                if (position.Character == value && !stringWalker.StateIs(StringWalkerState.InsideString))
                    return position.Index + startIndex;
            }

            return null;
        }

        public void FindsAMatchWhenThereIsOne()
        {
            string source = "Some!String";
            var matcher = new ExcludeStringMatcher(source);

            Assert.Equal(4, matcher.FindNextIndex('!'));
        }