[Tutor] Can a virtual environment be renamed?

[Chris Warrick]

On 16 April 2017 at 18:16, Jim <jf_byrnes at comcast.net> wrote:
> On 04/16/2017 10:10 AM, Chris Warrick wrote:
>>
>> On 16 April 2017 at 16:45, Jim <jf_byrnes at comcast.net> wrote:
>>>
>>> My system python is 2.7.12 so I created a virtual environment using venu
>>> to
>>> run 3.5.2. I put it in /home/jfb/EVs/env. Now I would like to try 3.6 and
>>> put it in env36. Is it possible to change env to env35 for 3.5.2 without
>>> breaking things?
>>
>>
>> No. You need to delete your existing virtualenv and create a new one.
>> You can just use `pip freeze > requirements.txt` in the old one and
>> run `pip install -r requirements.txt` in the new one to ”move” all the
>> packages you had.
>>
>>
>
> Thanks Chris. I thought that would be the answer but wanted to check before
> I spent a lot of time trying to do something that was not possible.
>
> Virtual environments tend to confuse me. My system is Mint 18.1 with 2.7.12
> & 3.5.2 installed. So I would have to download a tar file of 3.6, then build
> it and then use it's version of venv to create a virtual environment to try
> 3.6. Is that correct?

Yes, you need to install the appropriate interpreter first, and
likewise a virtualenv won’t work if you uninstall an
interpreter/upgrade it to a new minor version*. You might not need to
use the source tarball if
https://launchpad.net/~fkrull/+archive/ubuntu/deadsnakes works on Mint
(and if you do use tarballs, make sure to install somewhere in /opt or
whatever not to make a mess — it’s easy to break your OS if you’re not
careful)

* eg. 3.5 → 3.6. Won’t ever happen on Mint or other “friendly”
distros, unless you do a dist-upgrade. Happens pretty often on
rolling-release distros or macOS with homebrew.

-- 
Chris Warrick <https://chriswarrick.com/>
PGP: 5EAAEA16