Using regex to extract substrings enclosed in certain characters

Question

I'm trying to write a regex to capture all substrings in form of +++text+-- in a given input. So an example input could be:

Some text ++ not interesting text ++interesting part1-- and again some more text ++interesting part2-- and more text and ...

which I'd like to extract ++interesting part1-- and ++interesting part2--.

My regex attempts

1. Obviously ++.*?-- does not work. Because for input above it matches "++ not interesting text ++interesting part1--" which is wrong.

2. My other broken solution was the following regex ++(?!.*++).*-- which only captures the second instance ("interesting part2").

Any explanation and answer is welcome.

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Note: I do want to solve the issue with regex to master it, though I know the problem has easier solution by just looking for ++ and -- indices repeatedly.