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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 18:17:21 +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/826615647104df75e8b269e9999c290c75930c2e">826615647104df75e8b269e9999c290c75930c2e</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 number in condition</pre></dd>
<dt style="clear: both; float: left; font-weight: bold; width: 8em">Modified files</dt>
<dd style="margin-left: 8.5em">
<ul>
<li><a href="https://github.com/mroonga/mroonga/commit/826615647104df75e8b269e9999c290c75930c2e#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 (+18 -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/826615647104df75e8b269e9999c290c75930c2e#L0L466">...</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/826615647104df75e8b269e9999c290c75930c2e#L0L467">467</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/826615647104df75e8b269e9999c290c75930c2e#L0L468">468</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/826615647104df75e8b269e9999c290c75930c2e#L0L469">469</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/826615647104df75e8b269e9999c290c75930c2e#L0R466">...</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/826615647104df75e8b269e9999c290c75930c2e#L0R467">467</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/826615647104df75e8b269e9999c290c75930c2e#L0R468">468</a></span>
<span class="diff-line-number-not-changed" style="display: block; white-space: pre"><a href="https://github.com/mroonga/mroonga/commit/826615647104df75e8b269e9999c290c75930c2e#L0R469">469</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/826615647104df75e8b269e9999c290c75930c2e#L0R470">470</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/826615647104df75e8b269e9999c290c75930c2e#L0R471">471</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/826615647104df75e8b269e9999c290c75930c2e#L0R472">472</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/826615647104df75e8b269e9999c290c75930c2e#L0R473">473</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/826615647104df75e8b269e9999c290c75930c2e#L0R474">474</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/826615647104df75e8b269e9999c290c75930c2e#L0R475">475</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/826615647104df75e8b269e9999c290c75930c2e#L0R476">476</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/826615647104df75e8b269e9999c290c75930c2e#L0R477">477</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/826615647104df75e8b269e9999c290c75930c2e#L0R478">478</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/826615647104df75e8b269e9999c290c75930c2e#L0R479">479</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/826615647104df75e8b269e9999c290c75930c2e#L0R480">480</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/826615647104df75e8b269e9999c290c75930c2e#L0R481">481</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/826615647104df75e8b269e9999c290c75930c2e#L0R482">482</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/826615647104df75e8b269e9999c290c75930c2e#L0R483">483</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/826615647104df75e8b269e9999c290c75930c2e#L0R484">484</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/826615647104df75e8b269e9999c290c75930c2e#L0R485">485</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/826615647104df75e8b269e9999c290c75930c2e#L0R486">486</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/826615647104df75e8b269e9999c290c75930c2e#L0R487">487</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">@@ -467,3 +467,21 @@ <span class="diff-context" style="background-color: #ffffaa; color: #000000">bool型を用いる</span></span>
<span class="diff-not-changed" style="display: block; white-space: pre"> char *name = NULL;</span>
<span class="diff-not-changed" style="display: block; white-space: pre"> if (name == NULL) { ... }</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">+数値は比較する</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">+CやC++では ``0`` は偽、 ``0`` 以外は真の値となるが、条件式に数値を使う場合は ``strcmp(...) == 0`` などというように明示的に比較する。</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">+C++では真偽値に ``bool`` を使うためこのような状況は発生しないが、C言語由来のAPIでは ``int`` で真偽値を表現している場合が多い。しかし、 ``int`` だけでは真偽値として使っているか本当に数値として使っているかがわかりにくいため、 ``int`` のときはすべて数値として扱う。</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">+ if (memcmp(value1, value2, value_size) == 0) {</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+ printf("same value!\n");</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">+悪い例（ ``0`` を偽の値として扱っている）:</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">+ if (!memcmp(value1, value2, value_size)) {</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+ printf("same value!\n");</span>
<span class="diff-added" style="background-color: #aaffaa; color: #000000; display: block; white-space: pre">+ }</span>
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