How to group identical elements in Ruby array

Question

I have the following:

array = ["John", "Mike", "Bob", "Mike", "Bob"]

i want to get output:

[["Mike", "Mike"], ["Bob", "Bob"], ["John"]]

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sandstrom · Accepted Answer · 2019-09-26 15:46:05Z

55

Here is how to do that in Ruby.

array.group_by{ |x| x }.values

sandstrom

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answered Oct 4, 2012 at 10:36

sawa

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2 Comments

is there a way to do this with proc shorthand?

@maxpleaner you can do names = ["John", "Mike", "Bob", "Mike", "Bob"]; names.group_by(&:itself).values