Lucene.Net.Analysis.Synonym.SlowSynonymFilter.Match C# (CSharp) Method

        private SlowSynonymMap Match(SlowSynonymMap map)
        {
            SlowSynonymMap result = null;

            if (map.submap != null)
            {
                AttributeSource tok = NextTok();
                if (tok != null)
                {
                    // clone ourselves.
                    if (tok == this)
                    {
                        tok = CloneAttributes();
                    }
                    // check for positionIncrement!=1?  if>1, should not match, if==0, check multiple at this level?
                    var termAtt = tok.GetAttribute<ICharTermAttribute>();
                    SlowSynonymMap subMap = map.submap.Get(termAtt.Buffer(), 0, termAtt.Length);

                    if (subMap != null)
                    {
                        // recurse
                        result = Match(subMap);
                    }

                    if (result != null)
                    {
                        matched.AddFirst(tok);
                    }
                    else
                    {
                        // push back unmatched token
                        PushTok(tok);
                    }
                }
            }

            // if no longer sequence matched, so if this node has synonyms, it's the match.
            if (result == null && map.synonyms != null)
            {
                result = map;
            }

            return result;
        }