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<dt style="clear: both; float: left; font-weight: bold; width: 8em">Author</dt>
<dd style="margin-left: 8.5em">Kouhei Sutou <kou****@clear*****></dd>
<dt style="clear: both; float: left; font-weight: bold; width: 8em">Date</dt>
<dd style="margin-left: 8.5em">2012-03-15 17:51:24 +0900 (Thu, 15 Mar 2012)</dd>
<dt style="clear: both; float: left; font-weight: bold; width: 8em">New Revision</dt>
<dd style="margin-left: 8.5em"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb">52db33db18dddefc52a3c8037e2da75b023c18bb</a></dd>
<dt style="clear: both; float: left; font-weight: bold; width: 8em">Log</dt>
<dd style="margin-left: 8.5em"><pre style="border: 1px solid #aaa; font-family: Consolas, Menlo, "Liberation Mono", Courier, monospace; line-height: 1.2; padding: 0.5em">doc coding-style: add reasons about disabling copy constructor</pre></dd>
<dt style="clear: both; float: left; font-weight: bold; width: 8em">Modified files</dt>
<dd style="margin-left: 8.5em">
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<li><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#diff-0">doc/source/developer/coding_style.rst</a></li>
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<pre style="border: 0; font-family: Consolas, Menlo, "Liberation Mono", Courier, monospace; line-height: 1.2; margin: 0; padding: 0.5em; white-space: normal"><span class="diff-header" style="background-color: #eaf2f5; color: #999999; display: block; white-space: pre"> Modified: doc/source/developer/coding_style.rst (+5 -1)</span>
<span class="diff-header-mark" style="background-color: #eaf2f5; color: #999999; display: block; white-space: pre">===================================================================</span>
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<pre style="border: 0; font-family: Consolas, Menlo, "Liberation Mono", Courier, monospace; line-height: 1.2; margin: 0; padding: 0.5em; white-space: normal"><span class="diff-line-number-hunk-header" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L266">...</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L267">267</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L268">268</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L269">269</a></span>
<span class="diff-line-number-deleted" style="background-color: #ffaaaa; color: #000000; display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L270">270</a></span>
<span class="diff-line-number-nothing" style="display: block; white-space: pre"> </span>
<span class="diff-line-number-nothing" style="display: block; white-space: pre"> </span>
<span class="diff-line-number-nothing" style="display: block; white-space: pre"> </span>
<span class="diff-line-number-nothing" style="display: block; white-space: pre"> </span>
<span class="diff-line-number-nothing" style="display: block; white-space: pre"> </span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L271">271</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L272">272</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0L273">273</a></span>
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<pre style="border: 0; font-family: Consolas, Menlo, "Liberation Mono", Courier, monospace; line-height: 1.2; margin: 0; padding: 0.5em; white-space: normal"><span class="diff-line-number-hunk-header" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R266">...</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R267">267</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R268">268</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R269">269</a></span>
<span class="diff-line-number-nothing" style="display: block; white-space: pre"> </span>
<span class="diff-line-number-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R270">270</a></span>
<span class="diff-line-number-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R271">271</a></span>
<span class="diff-line-number-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R272">272</a></span>
<span class="diff-line-number-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R273">273</a></span>
<span class="diff-line-number-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R274">274</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R275">275</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R276">276</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/52db33db18dddefc52a3c8037e2da75b023c18bb#L0R277">277</a></span>
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<pre style="border: 0; font-family: Consolas, Menlo, "Liberation Mono", Courier, monospace; line-height: 1.2; margin: 0; padding: 0.5em; white-space: normal"><span class="diff-hunk-header" style="background-color: #eaf2f5; color: #999999; display: block; white-space: pre">@@ -267,7 +267,11 @@ <span class="diff-context" style="background-color: #ffffaa; color: #000000">TODO: ちゃんと考える。</span></span>
<span class="diff-not-changed" style="display: block; white-space: pre"> コピーコンストラクター</span>
<span class="diff-not-changed" style="display: block; white-space: pre"> ----------------------</span>
<span class="diff-not-changed" style="display: block; white-space: pre"> </span>
<span class="diff-deleted" style="background-color: #ffaaaa; color: #000000; display: block; white-space: pre">-基本的にコピーコンストラクターの使用を禁止する。</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+基本的にコピーコンストラクターの使用を禁止する。よほどのことがなければ使用しないこと。</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+コピーコンストラクターは暗黙的に無駄なコピーが発生する可能性があるためパフォーマンス上の問題がある。コピーではなくポインターやリファレンスを用いること。</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+また、デフォルトのコピーコンストラクター実装はメンバー変数のポインターの値をそのままコピーするため、デコンストラクターで二重に解放してしまう危険性がある。そのため、明示的にコピーコンストラクターを定義しない場合は無効にする。</span>
<span class="diff-not-changed" style="display: block; white-space: pre"> </span>
<span class="diff-not-changed" style="display: block; white-space: pre"> よい例:</span>
<span class="diff-not-changed" style="display: block; white-space: pre"> </span>
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