create an alias on ZSH but need to type it twice

Question

I'm trying to create an alias on ZSH.

The aim of the alias is to activate a python virtualenv.

I've put a line in my .zshrc

alias SOU="source /home/andykw/.zshrc && source $(setopt extendedglob &&  ls -d .^git/)/bin/activate"

Often I need to change virtual environment with activating a virtual environment in one of the folder, then switching to another folder and activate another virtual environment.

Example: Let's say I'm working with the folder flask_rest and I have to work on another project, django_rest, I will need to deactivate the flask_rest environment and activate the django_rest environment.

Instead of doing it several times with the command line source <folder_name>/bin/activate then go with another folder source <another_folder_name>/bin/activate, I only need to type SOU.

Hope it makes the context clearer.

PS: I'm using Ubuntu with a Windows Subsystem Linux.

Answer 1

Sounds like you want something like:

SOU() {
  set -o localoptions -o extendedglob
  local f
  for f (~/.zshrc ~/.(^git)/bin/activate(N.)) source $f || return
}

For SOU to source your ~/.zshrc and whatever file called bin/activate in hidden directories other than .git in your home directory (ignoring the fact that it doesn't seem to make much sense to me).

You may also want to add the U and r qualifiers to limit to files that you own, and that are readable by the owner.

That defines a function rather than an alias. Aliases are more for csh users. Bourne-like shells have proper programming constructs like functions, though aliases can still be useful there in some corner cases, when you do want it to be handled as text replacements or if the alias needs to do changes in the scope of the caller, none of which seem to be the case here.

You can either put that function definition in your ~/.zshrc or add it as an autoloadable function in one of your $fpath directories. See info zsh autoloading for details.

In any case sourcing ~/.zshrc does not undo what sourcing thosedirs/bin/activate files do. It just redoes whatever is in ~/.zshrc again (which could end up by undoing some of the changes brought by bin/activate but that would be by accident) and if some of those changings are additions, they will end-up accumulating among other problems.

Answer 2

If all you want is an alias that finds the single ./.*/bin/activate file in the current directory tree and sources it, then all you need is:

alias SOU='source. */bin/activate'

If the glob .*/bin/activate matches multiple files, only the first one will be sourced. Your ~/.zshrc file should be sourced every time you open a new non-login interactive shell session, and you probably don't want to be sourcing it multiple times. I suggest you open a new question to try and understand why you seem to need to source it explicitly.