Best Practices
---------------

A couple of Bash best practices summarized in a single page.

Note that most of the -o options have a shorter variant. Both are listed on this page.

All-in-one::

    set -euo pipefail
    if [[ "${DEBUG-0}" == "1" ]]; then set -x; fi

Note: to enable debug mode, run your script with ``DEBUG=1 ./my-script.sh``

Exit as soon as one command fails::

    set -e
    set -o errexit

Fail when accessing unset variables::

    set -u
    set -o nounset

Fail when any command from a pipeline fails::

    set -o pipefail

Optional debugging from argument::

    if [[ "${DEBUG-0}" == "1" ]]; then set -o xtrace; fi
    if [[ "${DEBUG-0}" == "1" ]]; then set -x; fi

    # Call with
    DEBUG=1 ./script.sh

Use double brackets ``[[ ]]`` for conditions::

    [[ 1 < 2 ]] && echo "1 is less than 2"

Why ? It supports ``<>``, ``&&``, ``||``, grouping expressions with ``( )``, pattern matching ``[[ $name = *c* ]]`` and regular expression ``[[ $name =~ ^Ali ]]``

Get the current script path::

    SCRIPTPATH="$( cd -- "$(dirname "$0")" >/dev/null 2>&1 ; pwd -P )"