You're seeing just the function integerize_values, go back to Cldr.Map module for more information.
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integerize_values(map, options \\ [])

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Transforms a map's String.t values to Integer.t values.


The map value is converted to an integer from either an atom or String.t only when the value is comprised of integer digits.

Keys which cannot be converted to an integer are returned unchanged.


iex> Cldr.Map.integerize_values %{a: %{b: "1"}}
%{a: %{b: 1}}