fn fn_contains_index_expr() {
arr := [1, 2, 3, 4, 5]
a := 1 in arr[ 0.. ]
_ := a
_ := 1 in arr[ ..2 ]
_ := 1 in arr[1..3]
d := arr[2]
_ := d
_ := arr[2 ..]
_ := arr[.. 2 ]
_ := arr[ 1 .. 3]
}