Terry <terry.yin...@gmail.com> wrote: > I'm trying to implement something like: > > remote_map(fun, list) > > to execute the function on a remove machine. But the problem is I > cannot pickle a lambda function and send it to the remote machine. > > Is there any possible way to pickle (or other method) any functions > including lambda? >
You can pickle any named functions that are declared at module scope. You cannot pickle anonymous functions, methods, or functions declared nested inside other functions. The function must be present in the same module when you unpickle it, and if the definition has changed between pickling and unpickling the new definition will be used (just as other instances will use the current class definition not the one they were pickled with). You probably could pickle some of the components needed to create your lambda and construct a new function from it when unpickling: try the code object, the name of the module to be used for the globals, and default arguments. I don't think you can pickle the closure so better make sure your lambda doesn't need one, and be very careful to ensure that you restore the pickle in the same version of Python otherwise the code object might break. Best just avoid this and use named functions for anything that needs pickling. -- Duncan Booth http://kupuguy.blogspot.com -- http://mail.python.org/mailman/listinfo/python-list
