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<h1>Parentheses and operator precedence</h1>
<p>In general an expression may be enclosed in parentheses without changing its meaning.</p>
<p>If parentheses are not used, operator precedence follows the sequence below, starting with the
operators that bind most tightly. Within each group the operators are evaluated left-to-right</p>
<table>
<tr>
<td content="para">
<p>
<b>Operator</b>
</p>
</td>
<td content="para">
<p>
<b>Meaning</b>
</p>
</td>
</tr>
<tr>
<td content="para">
<p>[]</p>
</td>
<td content="para">
<p>predicate</p>
</td>
</tr>
<tr>
<td content="para">
<p>/, //</p>
</td>
<td content="para">
<p>path operator</p>
</td>
</tr>
<tr>
<td content="para">
<p>unary -, unary +</p>
</td>
<td content="para">
<p>unary plus and minus</p>
</td>
</tr>
<tr>
<td content="para">
<p>cast as</p>
</td>
<td content="para">
<p>dynamic type conversion</p>
</td>
</tr>
<tr>
<td content="para">
<p>castable as</p>
</td>
<td content="para">
<p>type test</p>
</td>
</tr>
<tr>
<td content="para">
<p>treat as</p>
</td>
<td content="para">
<p>static type conversion</p>
</td>
</tr>
<tr>
<td content="para">
<p>instance of</p>
</td>
<td content="para">
<p>type test</p>
</td>
</tr>
<tr>
<td content="para">
<p>except, intersect</p>
</td>
<td content="para">
<p>set difference and intersection</p>
</td>
</tr>
<tr>
<td content="para">
<p>|, union</p>
</td>
<td content="para">
<p>union operation on sets</p>
</td>
</tr>
<tr>
<td content="para">
<p>*, div, idiv, mod</p>
</td>
<td content="para">
<p>multiply, divide, integer divide, modulo</p>
</td>
</tr>
<tr>
<td content="para">
<p>+, -</p>
</td>
<td content="para">
<p>plus, minus</p>
</td>
</tr>
<tr>
<td content="para">
<p>to</p>
</td>
<td content="para">
<p>range expression</p>
</td>
</tr>
<tr>
<td content="para">
<p>=, !=, is, <, <=;, >, >=, eq, ne, lt, le, gt, ge</p>
</td>
<td content="para">
<p>comparisons</p>
</td>
</tr>
<tr>
<td content="para">
<p>and</p>
</td>
<td content="para">
<p>Boolean and</p>
</td>
</tr>
<tr>
<td content="para">
<p>or</p>
</td>
<td content="para">
<p>Boolean or</p>
</td>
</tr>
<tr>
<td content="para">
<p>if</p>
</td>
<td content="para">
<p>conditional expressions</p>
</td>
</tr>
<tr>
<td content="para">
<p>some, every</p>
</td>
<td content="para">
<p>quantified expressions</p>
</td>
</tr>
<tr>
<td content="para">
<p>for</p>
</td>
<td content="para">
<p>iteration (mapping) over a sequence</p>
</td>
</tr>
<tr>
<td content="para">
<p>, (comma)</p>
</td>
<td content="para">
<p>Sequence concatenation</p>
</td>
</tr>
</table>
<p>The various operators are described, in roughly the above order, in the sections that follow.</p>
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<tr>
<td>
<p align="right"><a class="nav" href="filter.xml">Next</a></p>
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