Introduction to Arrays

An array is a data structure that stores a collection of elements sequentially in memory. Arrays are useful for storing multiple values of the same type, such as numbers, strings, or even custom data modules. In Flint, arrays are immutable by default in terms of references—assigning one array to another always creates a copy, not a reference.

Key Points About Flint Arrays

1. Arrays are always stored sequentially in memory, making access to their elements efficient.
2. Arrays are value types in Flint. This means copying an array creates a new, independent copy of its data.
3. If you modify an array inside a data object, you should access it directly using data.array instead of copying it out, as changes made to the copy won’t automatically reflect back in the original array.

Creating and Accessing Arrays

To declare a one-dimensional array, use the following syntax:

int[] arr; // Declare an uninitialized array
arr = int[5]; // Create an array with 5 elements initialized to the default value (0)

To assign values to specific elements or access them:

arr[0] = 10; // Set the first element to 10
int val = arr[0]; // Access the first element

Example: Using Arrays in Flint

def main():
    int[] arr = int[5]; // Create a 1D array of size 5
    arr[0] = 10;
    arr[1] = 20;
    print($"arr[0]: {arr[0]}, arr[1]: {arr[1]}");