Loop over tuples in bash?

Question

Is it possible to loop over tuples in bash?

As an example, it would be great if the following worked:

for (i,j) in ((c,3), (e,5)); do echo \"$i and $         


        

Answer 1

Use associative array (also known as dictionary/hashMap):

declare -A pairs=(
  [c]=3
  [e]=5
)
for key in "${!pairs[@]}"; do
  value="${pairs[$key]}"
  echo "key is $key and value is $value"
done

Works for bash4.0+.

---

If you need triples instead of pairs, you can use the more general approach:

animals=(dog cat mouse)
declare -A sound=(
  [dog]=barks
  [cat]=purrs
  [mouse]=cheeps
)
declare -A size=(
  [dog]=big
  [cat]=medium
  [mouse]=small
)
for animal in "${animals[@]}"; do
  echo "$animal ${sound[$animal]} and it is ${size[$animal]}"
done