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<h3>Methods</h3>
<ul class="link-list" role="directory">
<li ><a href="#method-i-def_delegator">#def_delegator</a>
<li ><a href="#method-i-def_delegators">#def_delegators</a>
<li ><a href="#method-i-def_single_delegator">#def_single_delegator</a>
<li ><a href="#method-i-def_single_delegators">#def_single_delegators</a>
<li ><a href="#method-i-delegate">#delegate</a>
<li ><a href="#method-i-single_delegate">#single_delegate</a>
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<h1 id="module-SingleForwardable" class="module">
module SingleForwardable
</h1>
<section class="description">
<p><a href="SingleForwardable.html"><code>SingleForwardable</code></a> can be used to setup delegation at the object level as well.</p>
<pre class="ruby"><span class="ruby-identifier">printer</span> = <span class="ruby-constant">String</span>.<span class="ruby-identifier">new</span>
<span class="ruby-identifier">printer</span>.<span class="ruby-identifier">extend</span> <span class="ruby-constant">SingleForwardable</span> <span class="ruby-comment"># prepare object for delegation</span>
<span class="ruby-identifier">printer</span>.<span class="ruby-identifier">def_delegator</span> <span class="ruby-string">"STDOUT"</span>, <span class="ruby-string">"puts"</span> <span class="ruby-comment"># add delegation for STDOUT.puts()</span>
<span class="ruby-identifier">printer</span>.<span class="ruby-identifier">puts</span> <span class="ruby-string">"Howdy!"</span>
</pre>
<p>Also, <a href="SingleForwardable.html"><code>SingleForwardable</code></a> can be used to set up delegation for a <a href="Class.html"><code>Class</code></a> or <a href="Module.html"><code>Module</code></a>.</p>
<pre class="ruby"><span class="ruby-keyword">class</span> <span class="ruby-constant">Implementation</span>
<span class="ruby-keyword">def</span> <span class="ruby-keyword">self</span>.<span class="ruby-identifier ruby-title">service</span>
<span class="ruby-identifier">puts</span> <span class="ruby-string">"serviced!"</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">module</span> <span class="ruby-constant">Facade</span>
<span class="ruby-identifier">extend</span> <span class="ruby-constant">SingleForwardable</span>
<span class="ruby-identifier">def_delegator</span> <span class="ruby-value">:Implementation</span>, <span class="ruby-value">:service</span>
<span class="ruby-keyword">end</span>
<span class="ruby-constant">Facade</span>.<span class="ruby-identifier">service</span> <span class="ruby-comment">#=> serviced!</span>
</pre>
<p>If you want to use both Forwardable and <a href="SingleForwardable.html"><code>SingleForwardable</code></a>, you can use methods def_instance_delegator and <a href="SingleForwardable.html#method-i-def_single_delegator"><code>def_single_delegator</code></a>, etc.</p>
</section>
<section id="5Buntitled-5D" class="documentation-section">
<section id="public-instance-5Buntitled-5D-method-details" class="method-section">
<header>
<h3>Public Instance Methods</h3>
</header>
<div id="method-i-def_delegator" class="method-detail method-alias">
<div class="method-heading">
<span class="method-name">def_delegator</span><span
class="method-args">(accessor, method, ali = method)</span>
</div>
<div class="method-description">
</div>
<div class="aliases">
Alias for: <a href="SingleForwardable.html#method-i-def_single_delegator">def_single_delegator</a>
</div>
</div>
<div id="method-i-def_delegators" class="method-detail method-alias">
<div class="method-heading">
<span class="method-name">def_delegators</span><span
class="method-args">(accessor, *methods)</span>
</div>
<div class="method-description">
</div>
<div class="aliases">
Alias for: <a href="SingleForwardable.html#method-i-def_single_delegators">def_single_delegators</a>
</div>
</div>
<div id="method-i-def_single_delegator" class="method-detail ">
<div class="method-heading">
<span class="method-callseq">
def_single_delegator(accessor, method, new_name=method)
</span>
<span class="method-click-advice">click to toggle source</span>
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<div class="method-description">
<p>Defines a method <em>method</em> which delegates to <em>accessor</em> (i.e. it calls the method of the same name in <em>accessor</em>). If <em>new_name</em> is provided, it is used as the name for the delegate method. Returns the name of the method defined.</p>
<div class="method-source-code" id="def_single_delegator-source">
<pre><span class="ruby-comment"># File lib/forwardable.rb, line 305</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">def_single_delegator</span>(<span class="ruby-identifier">accessor</span>, <span class="ruby-identifier">method</span>, <span class="ruby-identifier">ali</span> = <span class="ruby-identifier">method</span>)
<span class="ruby-identifier">gen</span> = <span class="ruby-constant">Forwardable</span>.<span class="ruby-identifier">_delegator_method</span>(<span class="ruby-keyword">self</span>, <span class="ruby-identifier">accessor</span>, <span class="ruby-identifier">method</span>, <span class="ruby-identifier">ali</span>)
<span class="ruby-identifier">ret</span> = <span class="ruby-identifier">instance_eval</span>(<span class="ruby-operator">&</span><span class="ruby-identifier">gen</span>)
<span class="ruby-identifier">singleton_class</span>.<span class="ruby-identifier">send</span>(<span class="ruby-value">:ruby2_keywords</span>, <span class="ruby-identifier">ali</span>) <span class="ruby-keyword">if</span> <span class="ruby-constant">RUBY_VERSION</span> <span class="ruby-operator">>=</span> <span class="ruby-string">'2.7'</span>
<span class="ruby-identifier">ret</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
<div class="aliases">
Also aliased as: <a href="SingleForwardable.html#method-i-def_delegator">def_delegator</a>
</div>
</div>
<div id="method-i-def_single_delegators" class="method-detail ">
<div class="method-heading">
<span class="method-name">def_single_delegators</span><span
class="method-args">(accessor, *methods)</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-description">
<p>Shortcut for defining multiple delegator methods, but with no provision for using a different name. The following two code samples have the same effect:</p>
<pre class="ruby"><span class="ruby-identifier">def_delegators</span> <span class="ruby-value">:@records</span>, <span class="ruby-value">:size</span>, <span class="ruby-value">:<<</span>, <span class="ruby-value">:map</span>
<span class="ruby-identifier">def_delegator</span> <span class="ruby-value">:@records</span>, <span class="ruby-value">:size</span>
<span class="ruby-identifier">def_delegator</span> <span class="ruby-value">:@records</span>, <span class="ruby-value">:<<</span>
<span class="ruby-identifier">def_delegator</span> <span class="ruby-value">:@records</span>, <span class="ruby-value">:map</span>
</pre>
<div class="method-source-code" id="def_single_delegators-source">
<pre><span class="ruby-comment"># File lib/forwardable.rb, line 291</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">def_single_delegators</span>(<span class="ruby-identifier">accessor</span>, <span class="ruby-operator">*</span><span class="ruby-identifier">methods</span>)
<span class="ruby-identifier">methods</span>.<span class="ruby-identifier">each</span> <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">method</span><span class="ruby-operator">|</span>
<span class="ruby-keyword">next</span> <span class="ruby-keyword">if</span> <span class="ruby-regexp">/\A__(?:send|id)__\z/</span> <span class="ruby-operator">=~</span> <span class="ruby-identifier">method</span>
<span class="ruby-identifier">def_single_delegator</span>(<span class="ruby-identifier">accessor</span>, <span class="ruby-identifier">method</span>)
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
<div class="aliases">
Also aliased as: <a href="SingleForwardable.html#method-i-def_delegators">def_delegators</a>
</div>
</div>
<div id="method-i-delegate" class="method-detail method-alias">
<div class="method-heading">
<span class="method-name">delegate</span><span
class="method-args">(hash)</span>
</div>
<div class="method-description">
</div>
<div class="aliases">
Alias for: <a href="SingleForwardable.html#method-i-single_delegate">single_delegate</a>
</div>
</div>
<div id="method-i-single_delegate" class="method-detail ">
<div class="method-heading">
<span class="method-callseq">
delegate method → accessor
</span>
<span class="method-click-advice">click to toggle source</span>
</div>
<div class="method-heading">
<span class="method-callseq">
delegate [method, method, ...] → accessor
</span>
</div>
<div class="method-description">
<p>Takes a hash as its argument. The key is a symbol or an array of symbols. These symbols correspond to method names. The value is the accessor to which the methods will be delegated.</p>
<div class="method-source-code" id="single_delegate-source">
<pre><span class="ruby-comment"># File lib/forwardable.rb, line 270</span>
<span class="ruby-keyword">def</span> <span class="ruby-identifier ruby-title">single_delegate</span>(<span class="ruby-identifier">hash</span>)
<span class="ruby-identifier">hash</span>.<span class="ruby-identifier">each</span> <span class="ruby-keyword">do</span> <span class="ruby-operator">|</span><span class="ruby-identifier">methods</span>, <span class="ruby-identifier">accessor</span><span class="ruby-operator">|</span>
<span class="ruby-keyword">unless</span> <span class="ruby-keyword">defined?</span>(<span class="ruby-identifier">methods</span>.<span class="ruby-identifier">each</span>)
<span class="ruby-identifier">def_single_delegator</span>(<span class="ruby-identifier">accessor</span>, <span class="ruby-identifier">methods</span>)
<span class="ruby-keyword">else</span>
<span class="ruby-identifier">methods</span>.<span class="ruby-identifier">each</span> {<span class="ruby-operator">|</span><span class="ruby-identifier">method</span><span class="ruby-operator">|</span> <span class="ruby-identifier">def_single_delegator</span>(<span class="ruby-identifier">accessor</span>, <span class="ruby-identifier">method</span>)}
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span>
<span class="ruby-keyword">end</span></pre>
</div>
</div>
<div class="aliases">
Also aliased as: <a href="SingleForwardable.html#method-i-delegate">delegate</a>
</div>
</div>
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