Array elements with spaces are arguments to a function

Question

myFunction()
{
    > /tmp/file_$1_$2
}

ELEMENTS=("first" "second" "a third" "a fourth")

for elem in "${ELEMENTS[@]}"
do
    myFunction "$elem"
done

I've tried the above code and a bunch of other variants found online:

BASH array with spaces in elements

Loop through array of arrays of string with spaces

https://unix.stackexchange.com/questions/181507/bash-script-array-elements-containing-space-character

But I could never get this to work. What I want my code to do is iterate over these elements:

1. first
2. second
3. a third
4. a fourth

pass them to myFunction but have the function treat for example a third as 2 arguments, not 1! So I would end up with 4 files:

1. /tmp/file_first_
2. /tmp/file_second_
3. /tmp/file_a_third
4. /tmp/file_a_fourth

Whatever I try it either treats every word as a different element (6 calls to myFunction) or treats e.g. a third as one argument and creates a file /tmp/file_a third_ or something different yet.

How do I do this right in bash?

Answer 1

If you want word splitting to occur, then you shouldn't quote your variable:

myFunction $elem

Here's an example, using printf to demonstrate:

$ elements=("first" "second" "a third" "a fourth")
$ func() { printf '/tmp/file_%s_%s\n' "$1" "$2"; }
$ for elem in "${elements[@]}"; do func $elem; done
/tmp/file_first_
/tmp/file_second_
/tmp/file_a_third
/tmp/file_a_fourth

Answer 2

Only remove double quotes when calling function:

myFunction $elem

The rest of code is ok.

However, you can try it using parameter expansion:

myFunction()
{
    > /tmp/file_${1// /_}
}

ELEMENTS=("first" "second" "a third" "a fourth")

for elem in "${ELEMENTS[@]}"
do
    myFunction "$elem"
done

I think this method can be better because if exists an element like this:

"a fifth ones"

myFunction() will create:

/tmp/file_a_fifth_ones

Explanation:

$ var1="I'm the content of a var"
$ echo "${var1// /_}"

Result:

I'm_the_content_of_a_var