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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">2012-03-16 10:13:14 +0900 (Fri, 16 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/a82f0ec8ef22f498835b3db61519daaeb58c28fe">a82f0ec8ef22f498835b3db61519daaeb58c28fe</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 about variable initialization</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/a82f0ec8ef22f498835b3db61519daaeb58c28fe#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 (+14 -0)</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/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0L519">...</a></span>
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<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0L521">521</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0L522">522</a></span>
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<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0L523">523</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0L524">524</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0L525">525</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/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R519">...</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R520">520</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R521">521</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R522">522</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/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R523">523</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/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R524">524</a></span>
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<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/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R531">531</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/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R532">532</a></span>
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<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/a82f0ec8ef22f498835b3db61519daaeb58c28fe#L0R539">539</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">@@ -520,6 +520,20 @@ <span class="diff-context" style="background-color: #ffffaa; color: #000000">C++では真偽値に ``bool`` を使うためこのような状況は発生し</span></span>
<span class="diff-not-changed" style="display: block; white-space: pre"> name_ = std::string(name);</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-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+変数宣言と同時に初期化する</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">+</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+変数を宣言したときに同時に初期化する。宣言時に初期化せずに代入して初期化すると、無駄な処理が発生する可能性があるため非効率である。（後述）</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">+よい例:</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">+ std::string name("users");</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">+悪い例（ ``std::string()`` のところでコンストラクターが動き、 ``name = ...`` のところで代入演算子が動いて2回初期化している）:</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">+ std::string name;</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+ name = std::string("users");</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+</span>
<span class="diff-not-changed" style="display: block; white-space: pre"> インクリメント・デクリメント</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>
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