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Move precedence table to syntax page.

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Bob Nystrom
2015-11-08 10:59:23 -08:00
parent 0bf5dc42ef
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@@ -125,5 +125,133 @@ same as doing:
return "single expression"
}
## Precedence and Associativity
We'll talk about Wren's different expression forms and what they mean in the
next few pages. But if you want to see how they interact with each other
grammatically, here's the whole table.
It shows which expressions have higher *precedence*—which ones bind more
tightly than others—and their *associativity*—how a series of the
same kind of expression is ordered. Wren mostly follows C, except that it fixes
[the bitwise operator mistake][mistake]. The full precedence table, from
tightest to loosest, is:
[mistake]: http://www.lysator.liu.se/c/dmr-on-or.html
<table class="precedence">
<tbody>
<tr>
<th>Prec</th>
<th>Operator</th>
<th>Description</th>
<th>Associates</th>
</tr>
<tr>
<td>1</td>
<td><code>()</code> <code>[]</code> <code>.</code></td>
<td>Grouping, <a href="method-calls.html">Subscript, Method call</a></td>
<td>Left</td>
</tr>
<tr>
<td>2</td>
<td><code>-</code> <code>!</code> <code>~</code></td>
<td><a href="method-calls.html#operators">Negate, Not, Complement</a></td>
<td>Right</td>
</tr>
<tr>
<td>3</td>
<td><code>*</code> <code>/</code> <code>%</code></td>
<td><a href="method-calls.html#operators">Multiply, Divide, Modulo</a></td>
<td>Left</td>
</tr>
<tr>
<td>4</td>
<td><code>+</code> <code>-</code></td>
<td><a href="method-calls.html#operators">Add, Subtract</a></td>
<td>Left</td>
</tr>
<tr>
<td>5</td>
<td><code>..</code> <code>...</code></td>
<td><a href="method-calls.html#operators">Inclusive range, Exclusive range</a></td>
<td>Left</td>
</tr>
<tr>
<td>6</td>
<td><code>&lt;&lt;</code> <code>&gt;&gt;</code></td>
<td><a href="method-calls.html#operators">Left shift, Right shift</a></td>
<td>Left</td>
</tr>
<tr>
<td>7</td>
<td><code>&lt;</code> <code>&lt;=</code> <code>&gt;</code> <code>&gt;=</code></td>
<td><a href="method-calls.html#operators">Comparison</a></td>
<td>Left</td>
</tr>
<tr>
<td>8</td>
<td><code>==</code></td>
<td><a href="method-calls.html#operators">Equals</a></td>
<td>Left</td>
</tr>
<tr>
<td>8</td>
<td><code>!=</code></td>
<td><a href="method-calls.html#operators">Not equal</a></td>
<td>Left</td>
</tr>
<tr>
<td>9</td>
<td><code>&amp;</code></td>
<td><a href="method-calls.html#operators">Bitwise and</a></td>
<td>Left</td>
</tr>
<tr>
<td>10</td>
<td><code>^</code></td>
<td><a href="method-calls.html#operators">Bitwise xor</a></td>
<td>Left</td>
</tr>
<tr>
<td>11</td>
<td><code>|</code></td>
<td><a href="method-calls.html#operators">Bitwise or</a></td>
<td>Left</td>
</tr>
<tr>
<td>12</td>
<td><code>is</code></td>
<td><a href="method-calls.html#operators">Type test</a></td>
<td>Left</td>
</tr>
<tr>
<td>13</td>
<td><code>&amp;&amp;</code></td>
<td><a href="control-flow.html#logical-operators">Logical and</a></td>
<td>Left</td>
</tr>
<tr>
<td>14</td>
<td><code>||</code></td>
<td><a href="control-flow.html#logical-operators">Logical or</a></td>
<td>Left</td>
</tr>
<tr>
<td>15</td>
<td><code>?:</code></td>
<td><a href="control-flow.html#the-conditional-operator-">Conditional</a></td>
<td>Right</td>
</tr>
<tr>
<td>16</td>
<td><code>=</code></td>
<td><a href="variables.html#assignment">Assignment</a>, <a href="method-calls.html#setters">Setter</a></td>
<td>Right</td>
</tr>
</tbody>
</table>
<a class="right" href="values.html">Values &rarr;</a>
<a href="getting-started.html">&larr; Getting Started</a>
<a href="getting-started.html">&larr; Getting Started</a>