How to return multiple arrays with function

Question

I wrote a function which returns an array:

create(){
   my_list=("a" "b" "c")
   echo "${my_list[@]}"
}

result=$(create)
for var in result
do
    echo $var
done

Now, I'd like to extend it in order to return multiple arrays. For example, I'd like to write something like that:

create(){
    my1=("1" "2")
    my2=("3","4")
    my3=("5","6")
     echo "${my1[@]} ${my3[@]} ${my3[@]}"
}

and I'd like to get each of the returned arrays:

 res1= ...
 res2= ...
 res3= ...

Anyone could suggest me a solution? Thanks

Why can't you just maintain a variable in global context, returning arrays is not the best of ways to design your code — Inian
– Inian, Commented Apr 26, 2017 at 11:32
If you can let us know your requirement, there are sure better ways to do this — Inian
– Inian, Commented Apr 26, 2017 at 11:33
Technically, you can't even return a single array; you can output the elements of one or more arrays. — chepner
– chepner, Commented Apr 26, 2017 at 11:39
Try setting my_list=("a b" "c d" "e f") inside create and see what happens. — chepner
– chepner, Commented Apr 26, 2017 at 11:49

chepner · Accepted Answer · 2017-04-26 11:53:53Z

1

You need to read with a while loop.

while read -r val1 val2; do
    arr1+=("$val1")
    arr2+=("$val2")
done < file.txt

There is no such thing as an array value in bash; you cannot use arrays the way you are attempting in your question. Consider this result:

create(){
   my_list=("a 1" "b 2" "c 3")
   echo "${my_list[@]}"
}

result=$(create)
for var in $result
do
    echo $var
done

This produces

a
1
b
2
c
3

not

a 1
b 2
c 3

answered Apr 26, 2017 at 11:53

chepner

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