[Python-Dev] PEP 397 (Python launcher for Windows) reference implementation

[Mark Hammond]

On 5/07/2011 11:23 AM, Greg Ewing wrote:
> Vinay Sajip wrote:
>> the installation of a pre-3.3 version of Python after Python 3.3 is
>> installed with the launcher will, if the user selects "Register
>> Extensions",
>> hijack the laumcher's associations to that earlier Python. Then bye
>> bye launcher
>
> I don't see how anything can be done about that. It
> also doesn't seem like too serious a problem -- it's
> no worse than what currently happens if you install an
> older version over a newer one, i.e. associations revert
> to the old version.
>
> Making the launcher a separate install at least offers
> a way of fixing that if it happens and isn't desired,
> i.e. reinstall the launcher.

Or an MSI installer may be able to offer a "repair" feature without too 
much pain.

However, I'm a bit torn on the separate installer issue.  I really think 
it should be installed with later Python versions even if it is made 
available as a separate installer for the benefit of earlier ones as it 
is one less step for people to get confused about - eg, in a few years 
when 3.3+ is the most common Python being downloaded and used, books or 
people helping on python-list could start referring to the launcher 
under the assumption it is installed, rather than avoiding mention of it 
simply to avoid the whole spiel about "this will only work if you have 
installed an optional package."  IOW, it will be impossible to give 
unconditional advice on certain aspects of launching Python.

If the launcher is such that we can unconditionally recommend its use, 
IMO we should just install it with Python.  I'll go with the consensus 
though...

Mark