Question

What is a Flexible Array, exactly?
I can’t find much on it.

Answer 1

A flexible array is an array whose index bounds are determined at run time and may change during the lifetime of the array.

Java arrays are flexible. For example, in Java you can assign one array to another:

int[] a1 = {1, 2, 3, 4};
int[] a2 = {1, 2, 3};
a1 = a2;

At first, a1 has index range 0–3, and a2 has index range 0–2.

After the assignment a1 = a2, a1 points to an array with index range 0–2, so the index range of a1 varied during the lifetime of a1.