https://guekka.github.io/js/lunr.jp.js

1/*!
2 * Lunr languages, `Japanese` language
3 * https://github.com/MihaiValentin/lunr-languages
4 *
5 * Copyright 2014, Chad Liu
6 * http://www.mozilla.org/MPL/
7 */
8/*!
9 * based on
10 * Snowball JavaScript Library v0.3
11 * http://code.google.com/p/urim/
12 * http://snowball.tartarus.org/
13 *
14 * Copyright 2010, Oleg Mazko
15 * http://www.mozilla.org/MPL/
16 */
17
18/**
19 * export the module via AMD, CommonJS or as a browser global
20 * Export code from https://github.com/umdjs/umd/blob/master/returnExports.js
21 */
22;
23(function(root, factory) {
24  if (typeof define === 'function' && define.amd) {
25    // AMD. Register as an anonymous module.
26    define(factory)
27  } else if (typeof exports === 'object') {
28    /**
29     * Node. Does not work with strict CommonJS, but
30     * only CommonJS-like environments that support module.exports,
31     * like Node.
32     */
33    module.exports = factory()
34  } else {
35    // Browser globals (root is window)
36    factory()(root.lunr);
37  }
38}(this, function() {
39  /**
40   * Just return a value to define the module export.
41   * This example returns an object, but the module
42   * can return a function as the exported value.
43   */
44  return function(lunr) {
45    /* throw error if lunr is not yet included */
46    if ('undefined' === typeof lunr) {
47      throw new Error('Lunr is not present. Please include / require Lunr before this script.');
48    }
49
50    /* throw error if lunr stemmer support is not yet included */
51    if ('undefined' === typeof lunr.stemmerSupport) {
52      throw new Error('Lunr stemmer support is not present. Please include / require Lunr stemmer support before this script.');
53    }
54
55    /* register specific locale function */
56    lunr.jp = function() {
57      this.pipeline.reset();
58      this.pipeline.add(
59        lunr.jp.stopWordFilter,
60        lunr.jp.stemmer
61      );
62      // change the tokenizer for japanese one
63      lunr.tokenizer = lunr.jp.tokenizer;
64    };
65    var segmenter = new TinySegmenter();  // インスタンス生成
66
67    lunr.jp.tokenizer = function (obj) {
68        if (!arguments.length || obj == null || obj == undefined) return []
69        if (Array.isArray(obj)) return obj.map(function (t) { return t.toLowerCase() })
70
71        var str = obj.toString().replace(/^\s+/, '')
72
73        for (var i = str.length - 1; i >= 0; i--) {
74            if (/\S/.test(str.charAt(i))) {
75                str = str.substring(0, i + 1)
76                break
77            }
78        }
79
80                     
81        var segs = segmenter.segment(str);  // 単語の配列が返る
82        return segs.filter(function (token) {
83            return !!token
84          })
85          .map(function (token) {
86            return token
87          })
88    }
89
90    /* lunr stemmer function */
91    lunr.jp.stemmer = (function() {
92      
93      /* TODO japanese stemmer  */
94      return function(word) {
95        return word;
96      }
97    })();
98
99    lunr.Pipeline.registerFunction(lunr.jp.stemmer, 'stemmer-jp');
100
101    /* stop word filter function */
102    lunr.jp.stopWordFilter = function(token) {
103      if (lunr.jp.stopWordFilter.stopWords.indexOf(token) === -1) {
104        return token;
105      }
106    };
107
108    lunr.jp.stopWordFilter.stopWords = new lunr.SortedSet();
109    lunr.jp.stopWordFilter.stopWords.length = 45;
110
111    // The space at the beginning is crucial: It marks the empty string
112    // as a stop word. lunr.js crashes during search when documents
113    // processed by the pipeline still contain the empty string.
114    // stopword for japanese is from http://www.ranks.nl/stopwords/japanese
115    lunr.jp.stopWordFilter.stopWords.elements = ' これ それ あれ この その あの ここ そこ あそこ こちら どこ だれ なに なん 何 私 貴方 貴方方 我々 私達 あの人 あのかた 彼女 彼 です あります おります います は が の に を で え から まで より も どの と し それで しかし'.split(' ');
116    lunr.Pipeline.registerFunction(lunr.jp.stopWordFilter, 'stopWordFilter-jp');
117  };
118}))