BASH_REMATCH doesn't capture

Question

I'm trying to capture a part of a path in bash:

Input: /Users/foo/.virtualenvs/venv-test-server

Code:

#!/bin/zsh
regex="^.*\/venv-(.*)$"
if [[ $VIRTUAL_ENV =~ $regex ]] ; then
  echo "Matched!"
  echo ${BASH_REMATCH[1]}
fi

Output: Matched!

But the match isn't printed. Why?

Answer 1

The script is specifying zsh instead of bash:

#!/bin/bash
       ^^^^

If you want to use zsh, you need to set BASH_REMATCH option before using =~:

setopt KSH_ARRAYS BASH_REMATCH

Answer 2

The equivalent array in zsh is match:

% [[ foo_bar =~ (.*)_(.*) ]]
% print $match[1]
foo
% print $match[2]
bar