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<li class="calls-super" ><a href="#method-c-new">::new</a>
<li ><a href="#method-i-weakref_alive-3F">#weakref_alive?</a>
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<h1 id="class-WeakRef" class="class">
class WeakRef
</h1>
<section class="description">
<p>Weak Reference class that allows a referenced object to be garbage-collected.</p>
<p>A <a href="WeakRef.html"><code>WeakRef</code></a> may be used exactly like the object it references.</p>
<p>Usage:</p>
<pre class="ruby"><span class="ruby-identifier">foo</span> = <span class="ruby-constant">Object</span>.<span class="ruby-identifier">new</span> <span class="ruby-comment"># create a new object instance</span>
<span class="ruby-identifier">p</span> <span class="ruby-identifier">foo</span>.<span class="ruby-identifier">to_s</span> <span class="ruby-comment"># original's class</span>
<span class="ruby-identifier">foo</span> = <span class="ruby-constant">WeakRef</span>.<span class="ruby-identifier">new</span>(<span class="ruby-identifier">foo</span>) <span class="ruby-comment"># reassign foo with WeakRef instance</span>
<span class="ruby-identifier">p</span> <span class="ruby-identifier">foo</span>.<span class="ruby-identifier">to_s</span> <span class="ruby-comment"># should be same class</span>
<span class="ruby-constant">GC</span>.<span class="ruby-identifier">start</span> <span class="ruby-comment"># start the garbage collector</span>
<span class="ruby-identifier">p</span> <span class="ruby-identifier">foo</span>.<span class="ruby-identifier">to_s</span> <span class="ruby-comment"># should raise exception (recycled)</span>
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<h3>Public Class Methods</h3>
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<div id="method-c-new" class="method-detail ">
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<span class="method-name">new</span><span
class="method-args">(orig)</span>
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<div class="method-description">
<p>Creates a weak reference to <code>orig</code></p>
<p>Raises an <a href="ArgumentError.html"><code>ArgumentError</code></a> if the given <code>orig</code> is immutable, such as <a href="Symbol.html"><code>Symbol</code></a>, <a href="Integer.html"><code>Integer</code></a>, or <a href="Float.html"><code>Float</code></a>.</p>
<div class="method-calls-super">
Calls superclass method
<a href="Delegator.html#method-c-new"><code>Delegator::new</code></a>
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<div class="method-source-code" id="new-source">
<pre><span class="ruby-comment"># File lib/weakref.rb, line 36</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">initialize</span>(<span class="ruby-identifier">orig</span>)
<span class="ruby-keyword">case</span> <span class="ruby-identifier">orig</span>
<span class="ruby-keyword">when</span> <span class="ruby-keyword">true</span>, <span class="ruby-keyword">false</span>, <span class="ruby-keyword">nil</span>
<span class="ruby-ivar">@delegate_sd_obj</span> = <span class="ruby-identifier">orig</span>
<span class="ruby-keyword">else</span>
<span class="ruby-identifier">@@__map</span>[<span class="ruby-keyword">self</span>] = <span class="ruby-identifier">orig</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">super</span>
<span class="ruby-keyword">end</span></pre>
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<h3>Public Instance Methods</h3>
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<div id="method-i-weakref_alive-3F" class="method-detail ">
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<span class="method-name">weakref_alive?</span><span
class="method-args">()</span>
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<div class="method-description">
<p>Returns true if the referenced object is still alive.</p>
<div class="method-source-code" id="weakref_alive-3F-source">
<pre><span class="ruby-comment"># File lib/weakref.rb, line 57</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">weakref_alive?</span>
<span class="ruby-identifier">@@__map</span>.<span class="ruby-identifier">key?</span>(<span class="ruby-keyword">self</span>) <span class="ruby-keyword">or</span> <span class="ruby-keyword">defined?</span>(<span class="ruby-ivar">@delegate_sd_obj</span>)
<span class="ruby-keyword">end</span></pre>
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