# if > Simple shell conditional. - Echo a different thing depending on a command's success: `{{command}} && echo "success" || echo "failure"` - Full if syntax: `if {{condition}}; then echo "true"; else echo "false"; fi` - List available if conditions: `help test` - Test if a given variable is empty: `if [[ -z $GIT_BRANCH ]]; then echo "true"; else echo "false"; fi` - Test if a file exists: `if [[ -e {{filename}} ]]; then echo "true"; else echo "false"; fi` - If directory not exists: `if [[ ! -d {{path/to/directory}} ]]; then echo "true"; else echo "false"; fi`