Making executable scripts source-friendly

sourceable.ps1

# This file can be sourced and also executed directly

# Definitions and declarations go here

function main () {
    # All action happens here
    return 0
}

# Only run if not sourced
if(!($MyInvocation.InvocationName -eq '.')) {
    main $args
}

sourceable.py

#!/usr/bin/python
# This file can be sourced and also executed directly

# Definitions and declarations go here

def main():
    # All action happens here
    return 0

# Only run if not sourced
if __name__ == '__main__':
    main()

sourceable.sh

#!/bin/bash
# This file can be sourced and also executed directly

# Definitions and declarations go here

main () {
    # All action happens here
    return 0
}

# Only run if not sourced
if [[ ${BASH_SOURCE[0]} == "$0" ]]; then
    main "$@"
fi