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@@ -563,84 +563,27 @@ Output 1
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### `length`
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+内置的函数 `length`会得到多种不同的类型值的长度:
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-The builtin function <code>length</code> gets the length of various different types of value:</p>
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-
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-<ul>
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-<li>
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-<p>The length of a <strong>string</strong> is the number of Unicode codepoints it contains (which will be the same as its JSON-encoded length in bytes if it’s pure ASCII).</p>
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-</li>
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-
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-<li>
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-<p>The length of an <strong>array</strong> is the number of elements.</p>
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-</li>
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-
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-<li>
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-<p>The length of an <strong>object</strong> is the number of key-value pairs.</p>
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-</li>
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-
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-<li>
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-<p>The length of <strong>null</strong> is zero.</p>
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-</li>
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-</ul>
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+ - **string** 的长度是这个字符串包含的unicode字符的个数(如果是纯ASCII的话，就和JSON-编码的字节的长度一样)
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+ - **array** 的长度就是元素的个数。
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+ - **object** 的长度是包含键值对的个数。
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+ - **null** 的长度是0
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+
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+[Examples](#example13)
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+```jq
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+ jq '.[] | length'
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+---------------------------
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+Input [[1,2], "string", {"a":2}, null]
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+Output 2
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+ 6
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+ 1
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+ 0
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+```
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-
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- <div>
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-
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- <a data-toggle="collapse" href="#example13">
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- <i class="glyphicon glyphicon-chevron-right"></i>
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- Example
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- </a>
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- <div id="example13" class="manual-example collapse">
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-
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- <table>
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- <tr><th></th><td class="jqprogram">jq '.[] | length'</td></tr>
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- <tr><th>Input</th><td>[[1,2], "string", {"a":2}, null]</td></tr>
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-
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-
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- <tr>
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-
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- <th>Output</th>
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-
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- <td>2</td>
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- </tr>
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-
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- <tr>
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-
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- <th></th>
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-
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- <td>6</td>
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- </tr>
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-
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- <tr>
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-
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- <th></th>
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-
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- <td>1</td>
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- </tr>
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-
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- <tr>
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-
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- <th></th>
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-
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- <td>0</td>
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- </tr>
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-
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- </table>
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-
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- </div>
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- </div>
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-
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- </section>
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-
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- <section id="keys,keys_unsorted">
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- <h3>
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-
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-<code>keys</code>, <code>keys_unsorted</code>
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+### `keys`,`keys_unsorted`
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-
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- </h3>
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<p>The builtin function <code>keys</code>, when given an object, returns its keys in an array.</p>
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alingse