Easiest way to check for an index or a key in an array?

Question

Using:

set -o nounset

1. Having an indexed array like:

   myArray=( "red" "black" "blue" )
            
   
   
           

Answer 1

What about a -z test and the :- operator?

For example, this script:

#!/usr/bin/env bash

set -e
set -u

declare -A sample

sample["ABC"]=2
sample["DEF"]=3

if [[ ! -z "${sample['ABC']:-}" ]]; then
  echo "ABC is set"
fi

if [[ ! -z "${sample['DEF']:-}" ]]; then
  echo "DEF is set"
fi

if [[ ! -z "${sample['GHI']:-}" ]]; then
  echo "GHI is set"
fi

Prints:

ABC is set
DEF is set