Bash: Is it possible to declare each list item on a new line?

Give a try to this tested version:

#!/bin/bash --
for var in  \
1 \
2 \
3 \
4 \
6 \
 ; do
  printf "%s\n" "${var}"
done

the for loop splits by default a string containing (spaces) and \n into separate elements.

' used in your for loop instructs the shell (in your version) to consider the parameter as one single value, a string containing several lines.

The test:

$ ./list.sh
1
2
3
4
6

The first version for reference:

#!/bin/bash --
listint='
1
2
3
4
6
'

for var in ${listint} ; do
  printf "%s\n" "${var}"
done

The ' enable to define string over multiple lines, including the \n.

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