Never forget to activate that virtualenv or set that environment variable ever again...
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Install pyenv brew install pyenv
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Install a few different pythons pyenv install 3.6.0 pyenv install 3.5.2 pyenv install 2.7.who-cares
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Install direnv brew install direnv
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If you're using zsh add the following to your ~/.zshrc:echo 'eval "$(direnv hook zsh)"' >> ~/.zshrc
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If you're using bassh add the following to your ~/.bashrc:echo 'eval "$(direnv hook bash)"' >> ~/.bashrc
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Copy .direnvrcinto~/
You now have everything setup to use direnv.
Now, time to actually use it.
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Create a directory, I usually put this in ~/workspace, others prefer!/projects.mkdir ~/projects/w00t
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Create the file ~/projects/w00t/.envrcecho "use python 3.6.0" > ~/projects/w00t/.envrc echo "export AN_ENVIRONMENT_VARIABLE=1" >> ~/projects/w00t/.envrc
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Go into that directory and say "yes, I trust this .envrc". You only need to do this when your .envrcfile changes.cd ~/projects/w00t direnv allowThis will cause a new python virtualenv to be created in ~/projects/w00t/.direnv
Now anytime you cd into ~/projects/w00t or a directory below that the virtualenv will automatically be enabled for you and environment variable AN_ENVIRONMENT_VARIABLE will be set.
w00t!