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<h1>snapshot.rb</h1>
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<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>
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<h1>Snapshot</h1>
<p>
A lightweight single-depth object state capture. The take_snapshot method
reads the object’s state, which is generally it’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("Customer", :name, :address, :zip)
joe = Customer.new( "Joe Pitare", "1115 Lila Ln.", 47634 )
# simple transactions
joe_snap = joe.take_snapshot
begin
do_something_with( joe )
rescue
joe.apply_snapshot( joe_snap )
end
joe_snap[:name] => "Joe Pitare"
joe_snap[:address] => "1115 Lila Ln."
joe_snap[:zip] => 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>’s will have symobl
keys while other classes will have string keys in the form of
"@name".
</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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