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<p class=MsoPlainText>Glyph,<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Thank you very much for your response, it has provided me
with material that will help me take a big step in my Twisted education.<o:p></o:p></p>
<p class=MsoPlainText>><o:p> </o:p></p>
<p class=MsoPlainText>> Deferreds are not about breaking your work up into
steps to save time.<o:p></o:p></p>
<p class=MsoPlainText>> They're about breaking it up so that different
systems can deal with<o:p></o:p></p>
<p class=MsoPlainText>> the<o:p></o:p></p>
<p class=MsoPlainText>> same asynchronous event in their own way.<o:p></o:p></p>
<p class=MsoPlainText>> <o:p></o:p></p>
<p class=MsoPlainText>> For example, let's say you're working on a REST
client that deals with<o:p></o:p></p>
<p class=MsoPlainText>> invoices. The server gives you data at a
particular URL and you want<o:p></o:p></p>
<p class=MsoPlainText>> to<o:p></o:p></p>
<p class=MsoPlainText>> convert it into an "Invoice" instance.<o:p></o:p></p>
<p class=MsoPlainText>> <o:p></o:p></p>
<p class=MsoPlainText>(snip)<o:p></o:p></p>
<p class=MsoPlainText>This whole section of your answer really helped me get a
handle on a deferred, well beyond the “promise that a function will have
a result later”. <span style='font-family:Wingdings'>J</span> I was
thinking kind of monolithically about how to use deferreds, in that if I was
writing everything why would I break it up? However, the real case is more
along the lines of what you said in your answer; more than likely the eventual
total behavior is made up of a string of smaller behaviors ‘glued’
together by the deferred. And these other behaviors would be code generated by
others in my group or libraries.<o:p></o:p></p>
<p class=MsoPlainText>(snip)<o:p></o:p></p>
<p class=MsoPlainText>> <o:p></o:p></p>
<p class=MsoPlainText>> If you actually wanted to interleave Deferred
callbacks like that it<o:p></o:p></p>
<p class=MsoPlainText>> would be tricky. But if you just want
interleaved callbacks, use<o:p></o:p></p>
<p class=MsoPlainText>> Cooperator as I mentioned above :).<o:p></o:p></p>
<p class=MsoPlainText>><o:p> </o:p></p>
<p class=MsoPlainText>This reference to the Cooperator really helped me out, I
just didn’t know what to look for in the Twisted system to do what I
wanted with co-operating state machines. I did build a little prototype using
deferreds that does provide the behavior I was after, but it was awkward at
best to set up. I felt like there should be something more elegant, and the
Cooperator looks like exactly what I need. I’m going to try and set up a
prototype to experiment with so I understand it more.<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
<p class=MsoPlainText>Again, thanks for your reply and help!<o:p></o:p></p>
<p class=MsoPlainText>Doug<o:p></o:p></p>
<p class=MsoPlainText><o:p> </o:p></p>
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