How to join merge/join two arrays in ballerina

Question

Lets say I have two int arrays.

1. How can I merge these two arrays?
2. How can I create a new array out of these two arrays?

Answer 1

1. To merge one array to another array, use array push function.
2. To merge two arrays and create a new array, use spread operator.

Sample code can be found in the below snippet.

import ballerina/io;

public function main() {
    int[] x = [1, 2];
    int[] y = [3, 4, 5];
    int[] z = [6, 7, 8];

    // Answer to Q1.
    // Pushes all of the members in `y` to x
    x.push(...y);
    // `x` changes now.
    io:println(x); // [1,2,3,4,5]
    // `y` remains the same.
    io:println(y); // [3,4,5]

    // Answer to Q2.
    // Creates a new list with the members from `x` and `y`.
    int[] arr = [...x, ...z];
    io:println(arr); // [1,2,3,4,5,6,7,8]

    io:println(x); // [1,2,3,4,5]
    io:println(y); // [3,4,5]
    io:println(z); // [6, 7, 8]
}