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    <h1>snapshot.rb</h1>
    <table class="header-table">
    <tr class="top-aligned-row">
      <td><strong>Path:</strong></td>
      <td>lib/carat/snapshot.rb
      </td>
    </tr>
    <tr class="top-aligned-row">
      <td><strong>Last Update:</strong></td>
      <td>Mon Apr 11 12:17:58 EDT 2005</td>
    </tr>
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      <h1>Snapshot</h1>
<p>
A lightweight single-depth object state capture. The take_snapshot method
reads the object&#8217;s state, which is generally it&#8217;s collection of
instance variables, and returns them in a hash. The state can be restored
with apply_snapshot.
</p>
<h2>Usage</h2>
<pre>
  require 'raspberry/new/snapshot'

  Customer = Struct.new(&quot;Customer&quot;, :name, :address, :zip)
  joe = Customer.new( &quot;Joe Pitare&quot;, &quot;1115 Lila Ln.&quot;, 47634 )

  # simple transactions
  joe_snap = joe.take_snapshot
  begin
    do_something_with( joe )
  rescue
    joe.apply_snapshot( joe_snap )
  end

  joe_snap[:name]     =&gt; &quot;Joe Pitare&quot;
  joe_snap[:address]  =&gt; &quot;1115 Lila Ln.&quot;
  joe_snap[:zip]      =&gt; 47634
</pre>
<h2>TODO</h2>
<ul>
<li>Perhaps extend to offer multiple depths.

</li>
<li>Should key consitancy be enforced? Currently <a
href="../../../classes/Struct.html">Struct</a>&#8217;s will have symobl
keys while other classes will have string keys in the form of
&quot;@name&quot;.

</li>
<li>Add other core classes.

</li>
</ul>
<h2>History</h2>
<ul>
<li>20005.04.11 Passed basic test.

</li>
</ul>
<h2></h2>

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