Map.pop-exclamation-mark

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Link to this function

pop!(map, key)

View Source (since 1.10.0)

Specs

pop!(map(), key()) :: {value(), updated_map :: map()}

Removes the value associated with key in map and returns the value and the updated map, or it raises if key is not present.

Behaves the same as pop/3 but raises if key is not present in map.

Examples

iex> Map.pop!(%{a: 1}, :a)
{1, %{}}
iex> Map.pop!(%{a: 1, b: 2}, :a)
{1, %{b: 2}}
iex> Map.pop!(%{a: 1}, :b)
** (KeyError) key :b not found in: %{a: 1}