On Mar 16, 2016, at 10:22, Chris Barker <chris.barker@noaa.gov> wrote:

On Wed, Mar 16, 2016 at 8:29 AM, Andrew Barnert via Python-ideas <python-ideas@python.org> wrote:
If this is only intended for rank beginners, what about just disabling the checkbox, with a warning, if there's already a program named "Python" anywhere on the PATH? Then, when someone gets into trouble because they're installing two Pythons, they'll get a warning and be able to ask their teacher or search StackOverflow 

please no -- it should be easy and obvious to "upgrade" python -- i.e. the last one you installed is what "just works".

If the default does that, then a non-defautl option to not override the existing one would be nice:

Warning: there is an existing python installed on this system: check here if you want to continue to have the old version be used as the default. Leve the box unchecked if you want the version to be the new default.

or something like that.

After all, what do people expect when they have MSWord version X, and then install MSWord version X+1 ? They expect that when they run Word after that, they'll get the new version. Is this going to surprise anyone???

Last time I did that, I ended up with Office 2007 in a completely separate directory from Office 2003, with their own Start Menu folders. The one under "Office" was still 2003, but there was a new one under "Microsoft Office" that I had to find. And Win-F "winword" still ran 2003. And .doc files were still owned by 2003 (but docx by 2007). And all of my system templates and most of my addons from 2003 weren't available in 2007 until I manually reinstalled them for it. And so on. I don't think anyone expects that with Office.

There are other kinds of apps where people _do_ expect it. For example, if you have TuneUp 2.4.3 and then install TuneUp 2.5.7, when you run a
TuneUp (whether via the Start menu, or Win-F, or because you had the "auto-start with iTunes checkbox on, etc.), you'll definitely get 2.5.7. But that's because 2.4.3 no longer exists on your system.

I don't think we want a Python 3.6 install to automatically uninstall or overwrite 2.7, or vice-versa. Which means it's like Office, not like TuneUp. Installing two Python versions on the same machine is always going to require some kind of management by the user.