Credo.Check.Refactor.MapJoin (Credo v1.7.13)

Basics

This check has a base priority of high and works with any version of Elixir.

Explanation

Enum.map_join/3 is more efficient than Enum.map/2 |> Enum.join/2.

This should be refactored:

["a", "b", "c"]
|> Enum.map(&String.upcase/1)
|> Enum.join(", ")

to look like this:

Enum.map_join(["a", "b", "c"], ", ", &String.upcase/1)

The reason for this is performance, because the two separate calls to Enum.map/2 and Enum.join/2 require two iterations whereas Enum.map_join/3 performs the same work in one pass.

Check-Specific Parameters

There are no specific parameters for this check.

General Parameters

Like with all checks, general params can be applied.

Parameters can be configured via the .credo.exs config file.