如何在阵列中分别选择2个项目，确保每个集合都已输出

Lets say I have an array of numbers: [1,2,3].

How can I loop through this array to create an array of possible permutations.

I'm expecting outputs like: [1,2], [1,3], [2,1], [2,3], [3,1], [3,2].