Check if a Bash array contains a value

Question

In Bash, what is the simplest way to test if an array contains a certain value?

Answer 1

Using parameter expansion:

${parameter:+word} If parameter is null or unset, nothing is substituted, otherwise the expansion of word is substituted.

declare -A myarray
myarray[hello]="world"

for i in hello goodbye 123
do
  if [ ${myarray[$i]:+_} ]
  then
    echo ${!myarray[$i]} ${myarray[$i]} 
  else
    printf "there is no %s\n" $i
  fi
done