Here is a small tip for ruby array operation
We have
a1 = ["a","b"]
a2 = ["b","c"]
Say we want to merge this two array to get a new array and it’s element must unique, you can
a3 = a1 + a2
a3.uniq!
# ["a","b","c"]
You can also do it like this
a1 | a2
# ["a","b","c"]
This is much quicker for our lazy fingers.