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Elixir List count of each unique element


There may come a time where you need to get a count of how many times a specific element occurs in a List. It might be needed for reporting, or to show to a user in an admin dashboard.

To accomplish this in Elixir you can use the Enum.frequencies/1 function. This function will take one argument, the enumerator, and return map with each unique element and it’s occurence count.

Enum.frequencies(["football", "baseball", "baseball", "hockey", "baseball"])
=> %{"baseball" => 3, "football" => 1, "hockey" => 1}

Further reading: