/// ------------------------------------------------------------------------------------
/// <summary>
/// Adds the given alternate (inflected) form of this word to the collection of words
/// that will be considered as equivalent words.
/// </summary>
/// ------------------------------------------------------------------------------------
public void AddAlternateForm(Word inflectedForm)
{
HashSet<Word> inflectedForms;
if (!s_inflectedWords.TryGetValue(this, out inflectedForms))
s_inflectedWords[this] = inflectedForms = new HashSet<Word>();
inflectedForms.Add(inflectedForm);
}
/// ------------------------------------------------------------------------------------
/// <summary>
/// Determines whether the specified other word is equivalent to this word (either the
/// same word or an inflected form of it).
/// </summary>
/// ------------------------------------------------------------------------------------
public bool IsEquivalent(Word otherWord)
{
if (this == otherWord)
return true;
HashSet<Word> inflectedForms;
return (s_inflectedWords.TryGetValue(this, out inflectedForms) && inflectedForms.Contains(otherWord));
}
public void AddWord(Word word)
{
if (word == null)
throw new ArgumentNullException("word");
m_words.Add(word);
}
/// ------------------------------------------------------------------------------------
/// <summary>
/// Gets all the possible surface forms represented by this metaword (which could have
/// an optional part, indicated by parentheses). If this is a completely optional word,
/// this will include a null. If it is part of an optional phrase, it will return an
/// empty list until it gets to the last word in the phrase, at which point it returns
/// a list representing the whole phrase.
/// </summary>
/// ------------------------------------------------------------------------------------
private List<Word> AllWords(Word metaWord, bool firstWordOfPhrase)
{
List<Word> list = new List<Word>();
int iOpenParen = (m_fInOptionalPhrase) ? 0 : metaWord.Text.IndexOf('(');
if (iOpenParen >= 0)
{
int iCloseParen = metaWord.Text.IndexOf(')', iOpenParen);
if (iCloseParen > iOpenParen)
{
if (m_fInOptionalPhrase)
{
list = m_optionalPhraseWords;
list.Add(metaWord.Text.Remove(iCloseParen));
m_optionalPhraseWords = null;
}
else
{
string opt = metaWord.Text.Remove(iOpenParen, iCloseParen - iOpenParen + 1);
list.Add(opt == string.Empty ? null : opt);
list.Add(metaWord.Text.Remove(iCloseParen, 1).Remove(iOpenParen, 1));
}
}
else if (m_fInOptionalPhrase)
{
m_optionalPhraseWords.Add(metaWord);
}
else if (iOpenParen == 0)
{
m_optionalPhraseWords = new List<Word>();
m_optionalPhraseWords.Add(metaWord.Text.Remove(0, 1));
m_fInOptionalPhrase = true;
}
else
{
Debug.Fail("Found opening parenthesis with no closer");
}
}
else
{
if (firstWordOfPhrase && metaWord == "to")
list.Add(null);
list.Add(metaWord);
}
return list;
}
/// ------------------------------------------------------------------------------------
/// <summary>
/// Finds the best key term in the list of words starting at m_iStartMatch and including
/// up to m_iNextWord. As new words are considered, the list possible matches
/// (m_matches) is reduced by any that no longer match until there is exactly one match
/// that exactly equals the words in the key term or the list is empty.
/// </summary>
/// ------------------------------------------------------------------------------------
private KeyTermMatch FindBestKeyTerm()
{
Word nextWord = m_words[m_iNextWord];
if (m_iStartMatch == m_iNextWord)
{
List <KeyTermMatch> matches;
if (!m_keyTermsTable.TryGetValue(nextWord, out matches))
{
Word stem = s_stemmer.stemTerm(nextWord);
if (m_keyTermsTable.TryGetValue(stem, out matches))
{
stem.AddAlternateForm(nextWord);
}
else
{
m_iStartMatch++;
return(null);
}
}
m_matches = new List <KeyTermMatch>(matches.Where(m => m.AppliesTo(m_phrase.StartRef, m_phrase.EndRef)));
// If we found a one-word exact match and there are no other key terms that start
// with that word, then we return it. The code below would handle this, but it's such
// a common case, we want it to be fast. If there are one or more multi-word key
// terms that start with this word, we need to keep looking.
if (m_matches.Count == 1 && m_matches[0].Words.Count() == 1)
{
return(m_matches[0]);
}
}
int cMatchingWordsInTermSoFar = m_iNextWord - m_iStartMatch + 1;
int lengthOfBestMatch = 0;
KeyTermMatch longestMatch = null;
// Remove from the possible matches any that don't match so far
for (int iTerm = 0; iTerm < m_matches.Count; iTerm++)
{
KeyTermMatch term = m_matches[iTerm];
if (!PhraseEqualsKeyTermSoFar(term, cMatchingWordsInTermSoFar) ||
(AtEndOfPhrase && term.m_words.Count > cMatchingWordsInTermSoFar))
{
m_matches.RemoveAt(iTerm--);
}
else if (term.m_words.Count > lengthOfBestMatch)
{
lengthOfBestMatch = term.m_words.Count;
longestMatch = term;
}
}
if (m_matches.Count == 0)
{
// The only matches we had were multi-word matches, and the addition of the current
// word made it so that none of them matched. Therefore, we don't have a key term
// starting at iStartMatch.
m_iNextWord = m_iStartMatch; // The for loop in Parse will increment this.
m_iStartMatch++;
return(null);
}
if ((m_matches.Count == 1 && lengthOfBestMatch < cMatchingWordsInTermSoFar) || (lengthOfBestMatch == cMatchingWordsInTermSoFar))
{
return(longestMatch);
}
return(null);
}
