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Atom.html
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Atom.html
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<!DOCTYPE html>
<html>
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Class: Concurrent::Atom
— Concurrent Ruby
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<div id="content"><h1>Class: Concurrent::Atom
</h1>
<div class="box_info">
<dl>
<dt>Inherits:</dt>
<dd>
<span class="inheritName"><span class='object_link'><a href="Synchronization/Object.html" title="Concurrent::Synchronization::Object (class)">Synchronization::Object</a></span></span>
<ul class="fullTree">
<li>Object</li>
<li class="next"><span class='object_link'><a href="Synchronization/Object.html" title="Concurrent::Synchronization::Object (class)">Synchronization::Object</a></span></li>
<li class="next">Concurrent::Atom</li>
</ul>
<a href="#" class="inheritanceTree">show all</a>
</dd>
</dl>
<dl>
<dt>Includes:</dt>
<dd><span class='object_link'><a href="Concern/Observable.html" title="Concurrent::Concern::Observable (module)">Concern::Observable</a></span></dd>
</dl>
<dl>
<dt>Defined in:</dt>
<dd>lib/concurrent/atom.rb</dd>
</dl>
</div>
<h2>Overview</h2><div class="docstring">
<div class="discussion">
<p>Atoms provide a way to manage shared, synchronous, independent state.</p>
<p>An atom is initialized with an initial value and an optional validation
proc. At any time the value of the atom can be synchronously and safely
changed. If a validator is given at construction then any new value
will be checked against the validator and will be rejected if the
validator returns false or raises an exception.</p>
<p>There are two ways to change the value of an atom: <span class='object_link'><a href="#compare_and_set-instance_method" title="Concurrent::Atom#compare_and_set (method)">#compare_and_set</a></span> and
<span class='object_link'><a href="#swap-instance_method" title="Concurrent::Atom#swap (method)">#swap</a></span>. The former will set the new value if and only if it validates and
the current value matches the new value. The latter will atomically set the
new value to the result of running the given block if and only if that
value validates.</p>
<h2>Example</h2>
<pre class="code ruby"><code class="ruby"><span class='kw'>def</span> <span class='id identifier rubyid_next_fibonacci'>next_fibonacci</span><span class='lparen'>(</span><span class='id identifier rubyid_set'>set</span> <span class='op'>=</span> <span class='kw'>nil</span><span class='rparen'>)</span>
<span class='kw'>return</span> <span class='lbracket'>[</span><span class='int'>0</span><span class='comma'>,</span> <span class='int'>1</span><span class='rbracket'>]</span> <span class='kw'>if</span> <span class='id identifier rubyid_set'>set</span><span class='period'>.</span><span class='id identifier rubyid_nil?'>nil?</span>
<span class='id identifier rubyid_set'>set</span> <span class='op'>+</span> <span class='lbracket'>[</span><span class='id identifier rubyid_set'>set</span><span class='lbracket'>[</span><span class='op'>-</span><span class='int'>2</span><span class='op'>..</span><span class='op'>-</span><span class='int'>1</span><span class='rbracket'>]</span><span class='period'>.</span><span class='id identifier rubyid_reduce'>reduce</span><span class='lbrace'>{</span><span class='op'>|</span><span class='id identifier rubyid_sum'>sum</span><span class='comma'>,</span><span class='id identifier rubyid_x'>x</span><span class='op'>|</span> <span class='id identifier rubyid_sum'>sum</span> <span class='op'>+</span> <span class='id identifier rubyid_x'>x</span> <span class='rbrace'>}</span><span class='rbracket'>]</span>
<span class='kw'>end</span>
<span class='comment'># create an atom with an initial value
</span><span class='id identifier rubyid_atom'>atom</span> <span class='op'>=</span> <span class='const'><span class='object_link'><a href="../Concurrent.html" title="Concurrent (module)">Concurrent</a></span></span><span class='op'>::</span><span class='const'>Atom</span><span class='period'>.</span><span class='id identifier rubyid_new'><span class='object_link'><a href="Synchronization/Object.html#new-class_method" title="Concurrent::Synchronization::Object.new (method)">new</a></span></span><span class='lparen'>(</span><span class='id identifier rubyid_next_fibonacci'>next_fibonacci</span><span class='rparen'>)</span>
<span class='comment'># send a few update requests
</span><span class='int'>5</span><span class='period'>.</span><span class='id identifier rubyid_times'>times</span> <span class='kw'>do</span>
<span class='id identifier rubyid_atom'>atom</span><span class='period'>.</span><span class='id identifier rubyid_swap'>swap</span><span class='lbrace'>{</span><span class='op'>|</span><span class='id identifier rubyid_set'>set</span><span class='op'>|</span> <span class='id identifier rubyid_next_fibonacci'>next_fibonacci</span><span class='lparen'>(</span><span class='id identifier rubyid_set'>set</span><span class='rparen'>)</span> <span class='rbrace'>}</span>
<span class='kw'>end</span>
<span class='comment'># get the current value
</span><span class='id identifier rubyid_atom'>atom</span><span class='period'>.</span><span class='id identifier rubyid_value'>value</span> <span class='comment'>#=> [0, 1, 1, 2, 3, 5, 8]
</span></code></pre>
<h2>Observation</h2>
<p>Atoms support observers through the Observable mixin module.
Notification of observers occurs every time the value of the Atom changes.
When notified the observer will receive three arguments: <code>time</code>, <code>old_value</code>,
and <code>new_value</code>. The <code>time</code> argument is the time at which the value change
occurred. The <code>old_value</code> is the value of the Atom when the change began
The <code>new_value</code> is the value to which the Atom was set when the change
completed. Note that <code>old_value</code> and <code>new_value</code> may be the same. This is
not an error. It simply means that the change operation returned the same
value.</p>
<p>Unlike in Clojure, <code>Atom</code> cannot participate in <span class='object_link'><a href="TVar.html" title="Concurrent::TVar (class)">TVar</a></span> transactions.</p>
<h2>Thread-safe Variable Classes</h2>
<p>Each of the thread-safe variable classes is designed to solve a different
problem. In general:</p>
<ul>
<li><em><span class='object_link'><a href="Agent.html" title="Concurrent::Agent (class)">Agent</a></span>:</em> Shared, mutable variable providing independent,
uncoordinated, <em>asynchronous</em> change of individual values. Best used when
the value will undergo frequent, complex updates. Suitable when the result
of an update does not need to be known immediately.</li>
<li><em><span class='object_link'><a href="" title="Concurrent::Atom (class)">Atom</a></span>:</em> Shared, mutable variable providing independent,
uncoordinated, <em>synchronous</em> change of individual values. Best used when
the value will undergo frequent reads but only occasional, though complex,
updates. Suitable when the result of an update must be known immediately.</li>
<li><em><span class='object_link'><a href="AtomicReference.html" title="Concurrent::AtomicReference (class)">AtomicReference</a></span>:</em> A simple object reference that can be
atomically. Updates are synchronous but fast. Best used when updates a
simple set operations. Not suitable when updates are complex.
<span class='object_link'><a href="AtomicBoolean.html" title="Concurrent::AtomicBoolean (class)">AtomicBoolean</a></span> and <span class='object_link'><a href="AtomicFixnum.html" title="Concurrent::AtomicFixnum (class)">AtomicFixnum</a></span> are similar
but optimized for the given data type.</li>
<li><em><span class='object_link'><a href="Exchanger.html" title="Concurrent::Exchanger (class)">Exchanger</a></span>:</em> Shared, stateless synchronization point. Used
when two or more threads need to exchange data. The threads will pair then
block on each other until the exchange is complete.</li>
<li><em><span class='object_link'><a href="MVar.html" title="Concurrent::MVar (class)">MVar</a></span>:</em> Shared synchronization point. Used when one thread
must give a value to another, which must take the value. The threads will
block on each other until the exchange is complete.</li>
<li><em><span class='object_link'><a href="ThreadLocalVar.html" title="Concurrent::ThreadLocalVar (class)">ThreadLocalVar</a></span>:</em> Shared, mutable, isolated variable which
holds a different value for each thread which has access. Often used as
an instance variable in objects which must maintain different state
for different threads.</li>
<li><em><span class='object_link'><a href="TVar.html" title="Concurrent::TVar (class)">TVar</a></span>:</em> Shared, mutable variables which provide
<em>coordinated</em>, <em>synchronous</em>, change of <em>many</em> stated. Used when multiple
value must change together, in an all-or-nothing transaction.</li>
</ul>
</div>
</div>
<div class="tags">
<p class="tag_title">See Also:</p>
<ul class="see">
<li><a href="http://clojure.org/atoms" target="_parent" title="Clojure Atoms">Clojure Atoms</a></li>
<li><a href="http://clojure.org/state" target="_parent" title="Values and Change - Clojure's approach to Identity and State">Values and Change - Clojure's approach to Identity and State</a></li>
</ul>
</div>
<h2>
Instance Method Summary
<small><a href="#" class="summary_toggle">collapse</a></small>
</h2>
<ul class="summary">
<li class="public ">
<span class="summary_signature">
<a href="#add_observer-instance_method" title="#add_observer (instance method)">#<strong>add_observer</strong>(observer = nil, func = :update, &block) ⇒ Object </a>
</span>
<span class="note title not_defined_here">
included
from <span class='object_link'><a href="Concern/Observable.html#add_observer-instance_method" title="Concurrent::Concern::Observable#add_observer (method)">Concern::Observable</a></span>
</span>
<span class="summary_desc"><div class='inline'><p>Adds an observer to this set.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#compare_and_set-instance_method" title="#compare_and_set (instance method)">#<strong>compare_and_set</strong>(old_value, new_value) ⇒ Boolean </a>
</span>
<span class="summary_desc"><div class='inline'><p>Atomically sets the value of atom to the new value if and only if the current value of the atom is identical to the old value and the new value successfully validates against the (optional) validator given at construction.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#count_observers-instance_method" title="#count_observers (instance method)">#<strong>count_observers</strong> ⇒ Integer </a>
</span>
<span class="note title not_defined_here">
included
from <span class='object_link'><a href="Concern/Observable.html#count_observers-instance_method" title="Concurrent::Concern::Observable#count_observers (method)">Concern::Observable</a></span>
</span>
<span class="summary_desc"><div class='inline'><p>Return the number of observers associated with this object.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#delete_observer-instance_method" title="#delete_observer (instance method)">#<strong>delete_observer</strong>(observer) ⇒ Object </a>
</span>
<span class="note title not_defined_here">
included
from <span class='object_link'><a href="Concern/Observable.html#delete_observer-instance_method" title="Concurrent::Concern::Observable#delete_observer (method)">Concern::Observable</a></span>
</span>
<span class="summary_desc"><div class='inline'><p>Remove <code>observer</code> as an observer on this object so that it will no longer receive notifications.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#delete_observers-instance_method" title="#delete_observers (instance method)">#<strong>delete_observers</strong> ⇒ Observable </a>
</span>
<span class="note title not_defined_here">
included
from <span class='object_link'><a href="Concern/Observable.html#delete_observers-instance_method" title="Concurrent::Concern::Observable#delete_observers (method)">Concern::Observable</a></span>
</span>
<span class="summary_desc"><div class='inline'><p>Remove all observers associated with this object.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#initialize-instance_method" title="#initialize (instance method)">#<strong>initialize</strong>(value, opts = {}) ⇒ Atom </a>
</span>
<span class="note title constructor">constructor</span>
<span class="summary_desc"><div class='inline'><p>Create a new atom with the given initial value.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#reset-instance_method" title="#reset (instance method)">#<strong>reset</strong>(new_value) ⇒ Object </a>
</span>
<span class="summary_desc"><div class='inline'><p>Atomically sets the value of atom to the new value without regard for the current value so long as the new value successfully validates against the (optional) validator given at construction.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#swap-instance_method" title="#swap (instance method)">#<strong>swap</strong>(*args) {|value, args| ... } ⇒ Object </a>
</span>
<span class="summary_desc"><div class='inline'><p>Atomically swaps the value of atom using the given block.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#value-instance_method" title="#value (instance method)">#<strong>value</strong> ⇒ Object </a>
(also: #deref)
</span>
<span class="summary_desc"><div class='inline'><p>The current value of the atom.</p>
</div></span>
</li>
<li class="public ">
<span class="summary_signature">
<a href="#with_observer-instance_method" title="#with_observer (instance method)">#<strong>with_observer</strong>(observer = nil, func = :update, &block) ⇒ Observable </a>
</span>
<span class="note title not_defined_here">
included
from <span class='object_link'><a href="Concern/Observable.html#with_observer-instance_method" title="Concurrent::Concern::Observable#with_observer (method)">Concern::Observable</a></span>
</span>
<span class="summary_desc"><div class='inline'><p>As <code>#add_observer</code> but can be used for chaining.</p>
</div></span>
</li>
</ul>
<div id="constructor_details" class="method_details_list">
<h2>Constructor Details</h2>
<div class="method_details first">
<h3 class="signature first" id="initialize-instance_method">
#<strong>initialize</strong>(value, opts = {}) ⇒ <tt><span class='object_link'><a href="" title="Concurrent::Atom (class)">Atom</a></span></tt>
</h3><div class="docstring">
<div class="discussion">
<p>Create a new atom with the given initial value.</p>
</div>
</div>
<div class="tags">
<p class="tag_title">Parameters:</p>
<ul class="param">
<li>
<span class='name'>value</span>
<span class='type'>(<tt>Object</tt>)</span>
—
<div class='inline'><p>The initial value</p>
</div>
</li>
<li>
<span class='name'>opts</span>
<span class='type'>(<tt><span class='object_link'><a href="Hash.html" title="Concurrent::Hash (class)">Hash</a></span></tt>)</span>
<em class="default">(defaults to: <tt>{}</tt>)</em>
—
<div class='inline'><p>The options used to configure the atom</p>
</div>
</li>
</ul>
<p class="tag_title">Options Hash (<tt>opts</tt>):</p>
<ul class="option">
<li>
<span class="name">:validator</span>
<span class="type">(<tt>Proc</tt>)</span>
<span class="default">
— default:
<tt>nil</tt>
</span>
— <div class='inline'><p>Optional proc used to validate new
values. It must accept one and only one argument which will be the
intended new value. The validator will return true if the new value
is acceptable else return false (preferrably) or raise an exception.</p>
</div>
</li>
<li>
<span class="name">:dup_on_deref</span>
<span class="type">(<tt>Boolean</tt>)</span>
<span class="default">
— default:
<tt>false</tt>
</span>
— <div class='inline'><p>Call <code>#dup</code> before
returning the data from <span class='object_link'><a href="#value-instance_method" title="Concurrent::Atom#value (method)">#value</a></span></p>
</div>
</li>
<li>
<span class="name">:freeze_on_deref</span>
<span class="type">(<tt>Boolean</tt>)</span>
<span class="default">
— default:
<tt>false</tt>
</span>
— <div class='inline'><p>Call <code>#freeze</code> before
returning the data from <span class='object_link'><a href="#value-instance_method" title="Concurrent::Atom#value (method)">#value</a></span></p>
</div>
</li>
<li>
<span class="name">:copy_on_deref</span>
<span class="type">(<tt>Proc</tt>)</span>
<span class="default">
— default:
<tt>nil</tt>
</span>
— <div class='inline'><p>When calling the <span class='object_link'><a href="#value-instance_method" title="Concurrent::Atom#value (method)">#value</a></span>
method, call the given proc passing the internal value as the sole
argument then return the new value returned from the proc.</p>
</div>
</li>
</ul>
<p class="tag_title">Raises:</p>
<ul class="raise">
<li>
<span class='type'>(<tt>ArgumentError</tt>)</span>
—
<div class='inline'><p>if the validator is not a <code>Proc</code> (when given)</p>
</div>
</li>
</ul>
</div><table class="source_code">
<tr>
<td>
<pre class="lines">
121
122
123
124
125
126</pre>
</td>
<td>
<pre class="code"><span class="info file"># File 'lib/concurrent/atom.rb', line 121</span>
<span class='kw'>def</span> <span class='id identifier rubyid_initialize'>initialize</span><span class='lparen'>(</span><span class='id identifier rubyid_value'>value</span><span class='comma'>,</span> <span class='id identifier rubyid_opts'>opts</span> <span class='op'>=</span> <span class='lbrace'>{</span><span class='rbrace'>}</span><span class='rparen'>)</span>
<span class='kw'>super</span><span class='lparen'>(</span><span class='rparen'>)</span>
<span class='ivar'>@Validator</span> <span class='op'>=</span> <span class='id identifier rubyid_opts'>opts</span><span class='period'>.</span><span class='id identifier rubyid_fetch'>fetch</span><span class='lparen'>(</span><span class='symbol'>:validator</span><span class='comma'>,</span> <span class='tlambda'>-></span> <span class='id identifier rubyid_v'>v</span> <span class='tlambeg'>{</span> <span class='kw'>true</span> <span class='rbrace'>}</span><span class='rparen'>)</span>
<span class='kw'>self</span><span class='period'>.</span><span class='id identifier rubyid_observers'>observers</span> <span class='op'>=</span> <span class='const'>Collection</span><span class='op'>::</span><span class='const'><span class='object_link'><a href="Collection/CopyOnNotifyObserverSet.html" title="Concurrent::Collection::CopyOnNotifyObserverSet (class)">CopyOnNotifyObserverSet</a></span></span><span class='period'>.</span><span class='id identifier rubyid_new'><span class='object_link'><a href="Collection/CopyOnNotifyObserverSet.html#initialize-instance_method" title="Concurrent::Collection::CopyOnNotifyObserverSet#initialize (method)">new</a></span></span>
<span class='kw'>self</span><span class='period'>.</span><span class='id identifier rubyid_value'>value</span> <span class='op'>=</span> <span class='id identifier rubyid_value'>value</span>
<span class='kw'>end</span></pre>
</td>
</tr>
</table>
</div>
</div>
<div id="instance_method_details" class="method_details_list">
<h2>Instance Method Details</h2>
<div class="method_details first">
<h3 class="signature first" id="add_observer-instance_method">
#<strong>add_observer</strong>(observer = nil, func = :update, &block) ⇒ <tt>Object</tt>
<span class="not_defined_here">
Originally defined in module
<span class='object_link'><a href="Concern/Observable.html#add_observer-instance_method" title="Concurrent::Concern::Observable#add_observer (method)">Concern::Observable</a></span>
</span>
</h3><div class="docstring">
<div class="discussion">
<p>Adds an observer to this set. If a block is passed, the observer will be
created by this method and no other params should be passed.</p>
</div>
</div>
<div class="tags">
<p class="tag_title">Parameters:</p>
<ul class="param">
<li>
<span class='name'>observer</span>
<span class='type'>(<tt>Object</tt>)</span>
<em class="default">(defaults to: <tt>nil</tt>)</em>
—
<div class='inline'><p>the observer to add</p>
</div>
</li>
<li>
<span class='name'>func</span>
<span class='type'>(<tt>Symbol</tt>)</span>
<em class="default">(defaults to: <tt>:update</tt>)</em>
—
<div class='inline'><p>the function to call on the observer during notification.
Default is :update</p>
</div>
</li>
</ul>
<p class="tag_title">Returns:</p>
<ul class="return">
<li>
<span class='type'>(<tt>Object</tt>)</span>
—
<div class='inline'><p>the added observer</p>
</div>
</li>
</ul>
</div>
</div>
<div class="method_details ">
<h3 class="signature " id="compare_and_set-instance_method">
#<strong>compare_and_set</strong>(old_value, new_value) ⇒ <tt>Boolean</tt>
</h3><div class="docstring">
<div class="discussion">
<p>Atomically sets the value of atom to the new value if and only if the
current value of the atom is identical to the old value and the new
value successfully validates against the (optional) validator given
at construction.</p>
</div>
</div>
<div class="tags">
<p class="tag_title">Parameters:</p>
<ul class="param">
<li>
<span class='name'>old_value</span>
<span class='type'>(<tt>Object</tt>)</span>
—
<div class='inline'><p>The expected current value.</p>
</div>
</li>
<li>
<span class='name'>new_value</span>
<span class='type'>(<tt>Object</tt>)</span>
—
<div class='inline'><p>The intended new value.</p>
</div>
</li>
</ul>
<p class="tag_title">Returns:</p>
<ul class="return">
<li>
<span class='type'>(<tt>Boolean</tt>)</span>
—
<div class='inline'><p>True if the value is changed else false.</p>
</div>
</li>
</ul>
</div><table class="source_code">
<tr>
<td>
<pre class="lines">
181
182
183
184
185
186
187
188</pre>
</td>
<td>
<pre class="code"><span class="info file"># File 'lib/concurrent/atom.rb', line 181</span>
<span class='kw'>def</span> <span class='id identifier rubyid_compare_and_set'>compare_and_set</span><span class='lparen'>(</span><span class='id identifier rubyid_old_value'>old_value</span><span class='comma'>,</span> <span class='id identifier rubyid_new_value'>new_value</span><span class='rparen'>)</span>
<span class='kw'>if</span> <span class='id identifier rubyid_valid?'>valid?</span><span class='lparen'>(</span><span class='id identifier rubyid_new_value'>new_value</span><span class='rparen'>)</span> <span class='op'>&&</span> <span class='id identifier rubyid_compare_and_set_value'>compare_and_set_value</span><span class='lparen'>(</span><span class='id identifier rubyid_old_value'>old_value</span><span class='comma'>,</span> <span class='id identifier rubyid_new_value'>new_value</span><span class='rparen'>)</span>
<span class='id identifier rubyid_observers'>observers</span><span class='period'>.</span><span class='id identifier rubyid_notify_observers'>notify_observers</span><span class='lparen'>(</span><span class='const'>Time</span><span class='period'>.</span><span class='id identifier rubyid_now'>now</span><span class='comma'>,</span> <span class='id identifier rubyid_old_value'>old_value</span><span class='comma'>,</span> <span class='id identifier rubyid_new_value'>new_value</span><span class='rparen'>)</span>
<span class='kw'>true</span>
<span class='kw'>else</span>
<span class='kw'>false</span>
<span class='kw'>end</span>
<span class='kw'>end</span></pre>
</td>
</tr>
</table>
</div>
<div class="method_details ">
<h3 class="signature " id="count_observers-instance_method">
#<strong>count_observers</strong> ⇒ <tt>Integer</tt>
<span class="not_defined_here">
Originally defined in module
<span class='object_link'><a href="Concern/Observable.html#count_observers-instance_method" title="Concurrent::Concern::Observable#count_observers (method)">Concern::Observable</a></span>
</span>
</h3><div class="docstring">
<div class="discussion">
<p>Return the number of observers associated with this object.</p>
</div>
</div>
<div class="tags">
<p class="tag_title">Returns:</p>
<ul class="return">
<li>
<span class='type'>(<tt>Integer</tt>)</span>
—
<div class='inline'><p>the observers count</p>
</div>
</li>
</ul>
</div>
</div>
<div class="method_details ">
<h3 class="signature " id="delete_observer-instance_method">
#<strong>delete_observer</strong>(observer) ⇒ <tt>Object</tt>
<span class="not_defined_here">
Originally defined in module
<span class='object_link'><a href="Concern/Observable.html#delete_observer-instance_method" title="Concurrent::Concern::Observable#delete_observer (method)">Concern::Observable</a></span>
</span>
</h3><div class="docstring">
<div class="discussion">
<p>Remove <code>observer</code> as an observer on this object so that it will no
longer receive notifications.</p>
</div>
</div>
<div class="tags">
<p class="tag_title">Parameters:</p>
<ul class="param">
<li>
<span class='name'>observer</span>
<span class='type'>(<tt>Object</tt>)</span>
—
<div class='inline'><p>the observer to remove</p>
</div>
</li>
</ul>
<p class="tag_title">Returns:</p>
<ul class="return">
<li>
<span class='type'>(<tt>Object</tt>)</span>
—
<div class='inline'><p>the deleted observer</p>
</div>
</li>
</ul>
</div>
</div>
<div class="method_details ">
<h3 class="signature " id="delete_observers-instance_method">
#<strong>delete_observers</strong> ⇒ <tt><span class='object_link'><a href="Concern/Observable.html" title="Concurrent::Concern::Observable (module)">Observable</a></span></tt>
<span class="not_defined_here">
Originally defined in module
<span class='object_link'><a href="Concern/Observable.html#delete_observers-instance_method" title="Concurrent::Concern::Observable#delete_observers (method)">Concern::Observable</a></span>
</span>
</h3><div class="docstring">
<div class="discussion">
<p>Remove all observers associated with this object.</p>
</div>
</div>
<div class="tags">
<p class="tag_title">Returns:</p>
<ul class="return">
<li>
<span class='type'>(<tt><span class='object_link'><a href="Concern/Observable.html" title="Concurrent::Concern::Observable (module)">Observable</a></span></tt>)</span>