> now I always used map() to perform a looped call on a function that > would change the attribute value, as shown in Mark Lutz & David > Ascher's Learning Python: > > # Perform attribute value change on a single instance > def iterateInstances( oInstance ): > oInstance.value = myValue > > # Loop over list of instances > map( iterateInstances, aListOfInstances )
How bizarre. I'm astonished that Lutz/Ascher even show that as a means of changing an attribute. As Danny said, it's definitely an abuse of map, and there is no advantage whatsoever, as far as I can see. In fact I suspect that it's actually slower than an explicit loop (because of the extra list building). > However I was looking into lambdas in hope to eliminate the need to > define a function. And a loop also avoids the need for a function, and therefore for a function call, which is another reason the map should be slower. Its completely weird that a text book should even suggest that map be used for this! Alan G Author of the Learn to Program web tutor http://www.freenetpages.co.uk/hp/alan.gauld _______________________________________________ Tutor maillist - Tutor@python.org http://mail.python.org/mailman/listinfo/tutor
