note BrowserUk <blockquote><i>I agree and as I said closures are somehow the other side of the OO coin in allowing encapsulated variables.</i></blockquote> <p>Indeed. [193628|One of my very early posts here] was a OO class that used closures to produce a JS-style prototypical OO mechanism. <p>Looking back at it I'm not sure it'll win any plaudits for maintainability, but it was a great tool for learning the power and limitations of closures. <blockquote><i> It's like saying why do we need lexical variables, as long as we care about chosing the right package-namespaces we can achieve the same. </i></blockquote> <p>I appreciate the analogy, but if you look back, I wasn't reaching any conclusions with my thoughts about closures, just examining the evidence. <p>As with many other ideas that suddenly gain currency -- despite usually having been around in one form or another since the '60s or early '70s -- I like to examine 'new ideas' every so often and try to see through the theory-wash, marketing speak and hyperbole, and reach my own conclusions as to their usefulness and importance. <P>Through this process I have avoided getting swept alone by many a fad that has subsequently shown itself to be of dubious value. I tend to apply the same criteria to most everything in life. <p>As far as closures go; I think I reached the conclusion that they are a valuable addition to languages so long as their implementation does not exact too high a price on the performance of the rest of that language. <p>Done right, they are a useful addition to the toolbox; but I wouldn't want to throw out (or ham-string performance-wise) too many of the other tools in the box to accommodate them. <p>Continuation passing on the other hand seems to exact too high a price. <blockquote><i>I think it's also part of the feature competition. </i></blockquote> <p>That's essentially what I was wondering. Are closures just another 'we must have that too' kick. <p>I think they are somewhat more than that. <blockquote><i> Saying this you might have noticed that some participants in this thread didn't really know what closure. </i></blockquote> <p>Indeed. But that is also true of many a dissertation on them that you'll find online. <P>But when I first encountered SmallTalk's <i>block arguments</i>; their significance was lost on me also. <div class="pmsig"><div class="pmsig-171588"> <hr /> <font size=1 > <div>With the rise and rise of 'Social' network sites: 'Computers are making people easier to use everyday'</div> <div>Examine what is said, not who speaks -- Silence betokens consent -- Love the truth but pardon error.</div> <div>"Science is about questioning the status quo. Questioning authority". </div> <div>In the absence of evidence, opinion is indistinguishable from prejudice. </div> </font> </div></div> 1018281 1018658