What about a simple "die" function that echoes a message and return an error code? Could be used both in scripts and in the interactive shell. It would use "exit" when SHLVL is more than 1, and "return" otherwise.
Scripts should not behave differently depending on if they were invoked from other scripts, and modular reusable libraries should never take it upon themselves to call "exit" when there's an error.
The way to control the flow of recursive functions is by passing explicit parameters (like the recursion depth, or a data structure to walk, or an error callback), not reflecting on the depth of the runtime stack or looking at how the function was called.
If bash is too weak to handle errors, or exceptions, or recursion, or passing functional callback parameters properly, or even file names with spaces in them, then use a better scripting language, don't just throw up your hands and exit.
https://stackoverflow.com/questions/14199689/how-can-i-handl...