tldr/pages/common/if.md

580 B

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