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POWhat do you call a method of an object that changes its class?
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copied!<p>Let's say you have a <code>Person</code> object and it has a method on it, <code>promote()</code>, that transforms it into a <code>Captain</code> object. What do you call this type of method/interaction?</p> <p>It also feels like an inversion of:</p> <pre><code>myCaptain = new Captain(myPerson); </code></pre> <p><strong>Edit:</strong> Thanks to all the replies. The reason I'm coming across this pattern (in Perl, but relevant anywhere) is purely for convenience. Without knowing any implementation deals, you could say the <code>Captain</code> class "has a" <code>Person</code> (I realize this may not be the best example, but be assured it isn't a subclass).</p> <p>Implementation I assumed:</p> <pre><code>// this definition only matches example A Person.promote() { return new Captain(this) } personable = new Person; // A. this is what i'm actually coding myCaptain = personable.promote(); // B. this is what my original post was implying personable.promote(); // is magically now a captain? </code></pre> <p>So, literally, it's just a convenience method for the construction of a <code>Captain</code>. I was merely wondering if this pattern has been seen in the wild and if it had a name. And I guess yeah, it doesn't really change the class so much as it returns a different one. But it theoretically could, since I don't really care about the original.</p> <p>Ken++, I like how you point out a use case. Sometimes it really would be awesome to change something in place, in say, a memory sensitive environment.</p>

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