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<body>
<section id="diary">
<h1>とある日の日記</h1>
<p>今日は、6月初めなのにとても暑い日だった。私の住む北海道の街では35度を超え、観測史上最速の猛暑日となった。この猛暑はフェーン現象<span class="annotations">【1】</span>が原因のようだ。この調子で景気も暖めて欲しいものである。いずれにせよ「試される大地」というキャッチフレーズが正に当てはまっている。<span class="annotations">【2】</span></p>
</section>
<aside>
<p class="footnotes">フェーン現象とは湿った風が山を越えて、暖かくて乾いた風となりに山の風下側の気温が上がる現象のこと。</p>
<p class="footnotes">「試される大地の"試される"は、「誰かが誰かを試す」というつらい意味での“試される”ではなく、「自らに問いかける」あるいは「世に問う」というプラス志向を示す言葉であるとともに前向きな挑戦する気持ち「TRY」の意味が込められている」だそうな・・・</p>
</aside>
</body>
body {
height: 2000px;
}
#diary {
height: 300px;
}
.annotations {
vertical-align: super;
font-size: 8px;
}
//脚注同士のリンクや説明を自動補完;
(function autocompleteAnnotations() {
var range = document.createRange();
//注釈側の処理;
(function() {
//注釈はannotationsというclass属性を持っている;
var annotations = document.getElementsByClassName('annotations');
var modelA = document.createElement('a');
modelA.id = 'annotation';
modelA.href = '#footnote';
for(var i = 0; i < annotations.length; i++) {
var a = modelA.cloneNode(true);
a.id += i;
a.href += i;
//注釈文字をa要素で囲む;
range.selectNodeContents(annotations[i]);
range.surroundContents(a);
}
})();
//脚注側の処理;
(function() {
//脚注はfootnotesというclass属性を持っている;
var footnotes = document.getElementsByClassName('footnotes');
var modelA = document.createElement('a');
modelA.id = 'footnote';
modelA.href = '#annotation';
for(var i = 0; i < footnotes.length; i++) {
//脚注を指している注釈側のtitle属性に同じ説明を加える;
var annotation = document.getElementById('annotation' + i);
annotation.title = footnotes[i].textContent;
var a = modelA.cloneNode(true);
a.id += i;
a.href += i;
a.textContent = annotation.textContent;
range.setStart(footnotes[i], 0);
range.insertNode(document.createTextNode(': '));
range.insertNode(a);
}
})();
range.detach();
})();
Also see: Tab Triggers