<html><body bgcolor="#FFFFFF"><div>I'd agree that the systems in these papers are far from ideal. In fact, the limitations they impose to make their type system work (linearity for example) are impractical for modeling wide classes of interesting problems. </div><div><br></div><div>For example, my day job involves distributed non-linear editing of linear media. There are a lot of adhoc states I need to represent in my models that have multiple states they can assume AND those states may depend on the sequence of prior states to determine which state comes next. </div><div><br></div><div><br></div><div>Dave<br><br>-=-=- <a href="mailto:dave@nexttolast.com">dave@nexttolast.com</a> -=-=-</div><div><br>On Sep 30, 2011, at 1:19 AM, <a href="mailto:ungar@mac.com">ungar@mac.com</a> wrote:<br><br></div><div></div><blockquote type="cite"><div>
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<p>Thanks, guys. I'll read the Ego paper. A while back I gave a keynote at OOPSLA on the role of paradox in language design.</p><div>In general, I believe that better type systems are worse--depending on the context. One loses the power of ambiguity.</div><div>However, if you are sending code to Mars, it's a good tradeoff. Anyway, I'll have to read the paper.</div><div><br></div><div>- David<br><div><br></div><div><br><div><div>On Sep 29, 2011, at 5:20 PM, David Goehrig wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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<div id="ygrp-text"><div><br class="webkit-block-placeholder"></div><div>The Plaid paper lays out the same concept with stricter typing. <br><br></div><div>I hadn't seen Ego before. </div><div><br></div><div>Thanks!</div><div><br>-=-=- <a href="mailto:dave@nexttolast.com"><a href="mailto:dave@nexttolast.com">dave@nexttolast.com</a></a> -=-=-</div><div><br>On Sep 29, 2011, at 3:47 PM, "Welch, Ronald P (US SSA)" <<a href="mailto:Ronald.P.Welch@BAESYSTEMS.com"><a href="mailto:Ronald.P.Welch@BAESYSTEMS.com">Ronald.P.Welch@BAESYSTEMS.com</a></a>> wrote:<br><br></div><div></div><blockquote type="cite"><div>
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<div id="ygrp-text"><p>Dave,</p><div><br></div><div>This reminds me of a derivation of Self called "Ego" that makes</div><div>steps toward adding type checking to Self. If you haven't </div><div>already seen it, there is paper describing Ego here:</div><div><br></div><div><a href="http://www.cs.cmu.edu/~aldrich/papers/"></a><a href="http://www.cs.cmu.edu/~aldrich/papers/"><a href="http://www.cs.cmu.edu/~aldrich/papers/">http://www.cs.cmu.edu/~aldrich/papers/</a></a></div><div><br></div><div>Ron</div><div><div>
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<br><div><div>On Sep 27, 2011, at 8:28 PM, David Goehrig wrote:</div><br class="Apple-interchange-newline"><blockquote type="cite">
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<div id="ygrp-text"><p>In one of the Self papers it states that assignable parent slots can be useful. And then it is largely an ignored subject from then on. <br>
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I've been ressurrecting this idea for a web framework which models core finite state machines by exploiting assignable parent slots to only expose methods sensible for that state. <br>
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eg. A response object has no header:Value: after the headers have already been sent, and a closed socket has no read or write: or close methods, but does have an open:<br>
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When I'm building these objects there is some default behavior that needs surpressing, specifically firing up the debugger when an unknown message send is encountered. This is heavily inspired by Randy's ARK unknown methods fall through. <br>
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Where this has become critical is building large scale distributed applications with transparent proxies forwarding messages. Which may hit an object multiple times due to resend logic. <br>
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Do any of the wise ones on the list know of any applications using these approaches?<br>
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If not, why?<br>
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-=-=- <a href="mailto:dave%40nexttolast.com"></a><a href="mailto:dave@nexttolast.com"><a href="mailto:dave@nexttolast.com">dave@nexttolast.com</a></a> -=-=-</p>
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