On Aug 26, 2010, at 12:25 PM, Jonny wrote:
I would propose that an idiomatic way is created, for instance a pragma or statement, which allows one to disambiguate the used python version in a manner that is both obvious for the human reader, and as well allows python to reject the script, should the wrong version of the interpreter be present. I think this is a quite common problem[1][2], which could be solved in a fairly easy and pragmatic way.
+1. I've found 3rd party libs where I only find out what version its compatible with by tripping over the wrong module. IMO it would be great for a pragma like Jonny mentions to be well supported. Here is a different take on mechanism and semantics. First, I'd like to be able to use: #!/usr/bin/python3 This allows a simple rough cut is a packaging issue, but IIRC the standard Makefile does not create python3. So the specific proposal is for the Makefile start doing that. This thread might be worth reading re: this issue. http://www.mail-archive.com/fedora-devel-list@redhat.com/msg08865.html Second, for the pragma, how about something like: __python__ = '2.4' When a new Python version sees that in the main script, a warning should be issued if __python__ is assigned a value that is lower than the current version or doesn't match the version format. In addition, if a module is imported with a higher version of __python__ than either the importing module or the main script, a warning should be issued. When a lint program sees that, any features not present in the version of python assigned to __python__ should be an error. In addition, lint programs should check the use of modules using the semantics that Python does. -Tony