47 lines
1.3 KiB
Go
47 lines
1.3 KiB
Go
// Copyright (c) 2014 Couchbase, Inc.
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// Licensed under the Apache License, Version 2.0 (the "License"); you may not use this file
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// except in compliance with the License. You may obtain a copy of the License at
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// http://www.apache.org/licenses/LICENSE-2.0
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// Unless required by applicable law or agreed to in writing, software distributed under the
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// License is distributed on an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND,
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// either express or implied. See the License for the specific language governing permissions
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// and limitations under the License.
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package stemmer_filter
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import (
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"bitbucket.org/tebeka/snowball"
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"github.com/couchbaselabs/bleve/analysis"
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)
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type StemmerFilter struct {
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lang string
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stemmer *snowball.Stemmer
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}
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func NewStemmerFilter(lang string) (*StemmerFilter, error) {
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stemmer, err := snowball.New(lang)
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if err != nil {
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return nil, err
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}
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return &StemmerFilter{
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lang: lang,
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stemmer: stemmer,
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}, nil
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}
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func (s *StemmerFilter) List() []string {
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return snowball.LangList()
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}
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func (s *StemmerFilter) Filter(input analysis.TokenStream) analysis.TokenStream {
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rv := make(analysis.TokenStream, 0)
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for _, token := range input {
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stemmed := s.stemmer.Stem(string(token.Term))
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token.Term = []byte(stemmed)
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rv = append(rv, token)
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}
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return rv
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}
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