// Stem extracts word's stem. Language/encoding of the word
// should match the algorithm/encoding of the created stemmer.
func (ws *WordStemmer) Stem(word []byte) ([]byte, error) {
ws.mutex.Lock()
defer ws.mutex.Unlock()
wordCString := C.CString(string(word))
defer C.free(unsafe.Pointer(wordCString))
// Stem the word
stemResult := C.sb_stemmer_stem(ws.stemmer,
(*C.sb_symbol)(unsafe.Pointer(wordCString)),
C.int(len(word)))
if nil == stemResult {
return nil, fmt.Errorf("Stemmer for (%s;%s) cannot extract stem for word: '%s'",
ws.algorithm,
ws.encoding,
word)
}
stemLen := C.sb_stemmer_length(ws.stemmer)
if stemLen <= 0 ||
stemLen > MaxAllowedStemLength {
return nil, fmt.Errorf("Stemmer for (%s;%s) got incorrect stem length for word: '%s': len = '%d'",
ws.algorithm,
ws.encoding,
word,
stemLen)
}
return C.GoBytes(unsafe.Pointer(stemResult), stemLen), nil
}
// Stem returns them stem of word (e.g. running -> run)
func (stmr *Stemmer) Stem(word string) string {
ptr := unsafe.Pointer(C.CString(word))
defer C.free(ptr)
w := (*C.sb_symbol)(ptr)
res := unsafe.Pointer(C.sb_stemmer_stem(stmr.stmr, w, C.int(len(word))))
size := C.sb_stemmer_length(stmr.stmr)
buf := C.GoBytes(res, size)
return string(buf)
}