In response to my question, ``What is the idiomatically appropriate Python way to pass, as a "function-type parameter", code that is most clearly written with a local variable?'', a number of you made very helpful suggestions, including the use of a default argument; if one wanted to give a name to the constant one in my original example,
map(lambda x: x+1, [5, 17, 49.5]) one would write map(lambda x, one=1: x+one, [5, 17, 49.5]) I've been using this happily in several cases, but just discovered that (of course), the variable "x" is not in scope until the expression in the lambda, so if one wanted to, say, have a variable that was 3*x, one could NOT write map(lambda x, threex=3*x: x+threex, [5, 17, 49.5]) [obviously there are easier ways to find 4*x, but I'm trying to keep close to my simplified example]. I'll need to show the code to beginners, so I don't want to get into the complexity of using the more advanced solutions that were suggested (closures or callable classes), so I'm going to bail out in such cases and just not use an anonymous function here. I'm not sure there's really a question here, other than the implicit "please let me know if there's yet another cool thing I can do here", but I thought I'd add this postscript to my earlier postings for the benefit of anyone following this thread. [I often see interesting threads in the archive but am left with an unresolved question "I wonder how that worked out"]. Dave Wonnacott -- http://mail.python.org/mailman/listinfo/python-list
