Add / Remove key-value pairs from a Map

Question

How to add (and remove) key-value pairs in an Elixir map? This does not work: ``` map = %{a: 1, b: 2, c: 3} map[:d] = 4 ```

Accepted Answer

Add to Map

Use `Map.put(map, key, value)`:

```
map = Map.put(map, :d, 4)
#=> %{a: 1, b: 2, c: 3, d: 4}
```

Remove from Map

Use `Map.delete(map, key)`:

```
map = Map.delete(map, :b)
#=> %{a: 1, c: 3}
```

Solution