freeCodeCamp/guide/english/elixir/maps/index.md

title
Maps

Maps

Maps is the Elixir data structure for key-values. They are not ordered and allow keys of any type. Maps are created using the %{} syntax:

iex(1)> %{}
%{}
iex(2)> %{1 => "one", 2 => "two", 3 => "three"}
%{1 => "one", 2 => "two", 3 => "three"}

Maps can be accessed with Map.get/3 or Map.fetch/2 or with through the map[] syntax:

iex(1)> map=%{1 => "one", 2 => "two"}
%{1 => "one", 2 => "two"}
iex(2)> Map.fetch(map, 1)
{:ok, "one"}
iex(3)> map[2]
"two"
iex(4)> map[5]
nil

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