Bash split string on delimiter, assign segments to array

Question

In bash, I would like to transform a PATH-like environment variable that may contain space-separated elements into an array, making sure eleme

Answer 1

f() {
  local IFS=:
  local foo
  set -f # Disable glob expansion
  foo=( $@ ) # Deliberately unquoted 
  set +f
  printf '%d\n' "${#foo[@]}"
  printf '%s\n' "${foo[@]}"
}

f 'un:dodecaedro:per:tirare:per:i danni'
6
un
dodecaedro
per
tirare
per
i danni

Modifying Jim McNamara's answer, you could just reset IFS:

oIFS="$IFS"
foo='un:dodecaedro:per:tirare:per:i danni'
IFS=: arr=( $foo )
IFS="$oIFS"

I prefer the function scope because it protects IFS changes from bleeding into the global scope without requiring special care to reset it.

Edits and explanations:

As a matter of clarification: In the second example, the IFS setting does change the global variable. The salient difference between this:

IFS=: arr=( $foo )

and this:

IFS=: read -a arr <<< "$foo"

is that the former is two variable assignments and no commands, and the latter is a simple command (see simple command in man (1) bash.)

Demonstration:

$ echo "$BASH_VERSION"
3.2.48(1)-release
$ echo "$IFS"


$ foo='un:dodecaedro:per:tirare:per:i danni'
$ IFS=: read -a arr <<< "$foo"
$ echo "${#arr[@]}"
6
$ echo "$IFS"


$ IFS=: arr1=( $foo )
$ echo "${#arr1[@]}"
6
$ echo "$IFS"
: