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<main role="main" aria-label="Page syntax/precedence.rdoc">
<h1 id="label-Precedence">Precedence<span><a href="#label-Precedence">¶</a> <a href="#top">↑</a></span></h1>
<p>From highest to lowest, this is the precedence table for ruby. High precedence operations happen before low precedence operations.</p>
<pre>!, ~, unary +
**
unary -
*, /, %
+, -
<<, >>
&
|, ^
>, >=, <, <=
<=>, ==, ===, !=, =~, !~
&&
||
.., ...
?, :
modifier-rescue
=, +=, -=, etc.
defined?
not
or, and
modifier-if, modifier-unless, modifier-while, modifier-until
{ } blocks</pre>
<p>Unary <code>+</code> and unary <code>-</code> are for <code>+1</code>, <code>-1</code> or <code>-(a + b)</code>.</p>
<p>Modifier-if, modifier-unless, etc. are for the modifier versions of those keywords. For example, this is a modifier-unless statement:</p>
<pre class="ruby"><span class="ruby-identifier">a</span> <span class="ruby-operator">+=</span> <span class="ruby-value">1</span> <span class="ruby-keyword">unless</span> <span class="ruby-identifier">a</span>.<span class="ruby-identifier">zero?</span>
</pre>
<p>Note that <code>(a if b rescue c)</code> is parsed as <code>((a if b) rescue c)</code> due to reasons not related to precedence. See <a href="control_expressions_rdoc.html#label-Modifier+Statements">modifier statements</a>.</p>
<p><code>{ ... }</code> blocks have priority below all listed operations, but <code>do ... end</code> blocks have lower priority.</p>
<p>All other words in the precedence table above are keywords.</p>
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