Question

I’m looking to be able to always execute both validateA and validateB:

function validateA() {
  echo "A [ok]"
  return 0
}

function validateB() {
  echo "B [ok]"
  return 0
}

if ! validateA | ! validateB; then 
  echo "validation [fail]"
  exit 1
else
  echo "validation [ok]"
  exit 0
fi

Answer 1

You can just call them regardless and capture the return values:

function validateA() {
    echo "A [fail]"
    return 1
}

function validateB() {
    echo "B [ok]"
    return 0
}

validateA ; vA=$?
validateB ; vB=$?

if [[ $vA -ne 0 || $vB -ne 0 ]] ; then
    echo "validation [fail]"
    exit 1
else
    echo "validation [ok]"
    exit 0
fi

This outputs:

A [fail]
B [ok]
validation [fail]