Base bash "print and exit on error" utility functions

bash_utils.sh

#!/bin/bash

#
# Prints the given command, then executes it
#  Example: print_and_do_command echo 'hi'
#
function print_and_do_command {
	echo " -> $ $@"
	$@
}

#
# Print the given command, execute it
#	and exit if error happened
function print_and_do_command_exit_on_error {
	print_and_do_command $@
	if [ $? -ne 0 ]; then
		echo " [!] Failed!"
		exit 1
	fi
}

#
# Check the last command's result code and if it's not zero
#	then print the given error message and exit with the command's exit code
#
function fail_if_cmd_error {
	local last_cmd_result=$?
	local error_msg="$1"
	if [ ${last_cmd_result} -ne 0 ]; then
		echo " [!] ${error_msg}"
		exit ${last_cmd_result}
	fi
}



# example with 'print_and_do_command_exit_on_error':
print_and_do_command_exit_on_error brew install git

# OR with the combination of 'print and do' and 'fail':
print_and_do_command brew install git
fail_if_cmd_error "Failed to install git!"