Specs

avg(list() | map(), (any() -> number())) :: number()

Calculates the average of values in an enumerable. Currently supports maps and lists only.

Examples

iex> Swiss.Enum.avg([1, 2, 3, 4])
2.5

iex> Swiss.Enum.avg([%{key: 1}, %{key: 2}, %{key: 3}, %{key: 4}], & &1.key)
2.5

iex> Swiss.Enum.avg(%{a: 1, b: 2, c: 3, d: 4}, &elem(&1, 1))
2.5

iex> Swiss.Enum.avg(%{})
0

iex> Swiss.Enum.avg([])
0

Finds an element and its index in enumerable for which fun returns true.

Examples

iex> Swiss.Enum.find_both([42, 44, 46], fn num -> num == 44 end)
{44, 1}

iex> Swiss.Enum.find_both([42, 44, 46], fn num -> num == 45 end)
{nil, nil}

Specs

find_by(Enumerable.t(), any(), any(), any()) :: any()

Finds the first element in enumerable where its key equals value.

Returns default if not found.

Examples

iex> Swiss.Enum.find_by([%{life: 11}, %{life: 42}], :life, 42)
%{life: 42}

iex> Swiss.Enum.find_by([%{life: 11}, %{life: 42}], :wat, 42)
nil

iex> Swiss.Enum.find_by([%{life: 11}, %{life: 42}], 42, :wat, 42)
42

iex> Swiss.Enum.find_by([%Swiss.TestStruct{life: 42}], :life, 42)
%Swiss.TestStruct{life: 42}

Specs

find_by!(Enumerable.t(), any(), any()) :: any()

Finds the first element in enumerable where its key equals value.

Raises if not found.

Examples

iex> Swiss.Enum.find_by!([%{life: 11}, %{life: 42}], :life, 42)
%{life: 42}

iex> Swiss.Enum.find_by!([%{life: 11}, %{life: 42}], :wat, 42)
** (Swiss.Enum.KeyValueError) key :wat with value 42 not found in: [%{life: 11}, %{life: 42}]

Specs

group_by_single(Enumerable.t(), (any() -> any()), (any() -> any())) :: map()

Same as Enum.group_by/3 but expects each group to have a single element, and therefore returns only that element per key, instead of a list.

Examples

iex> Swiss.Enum.group_by_single(
...>   [%{k: "life", v: 42}, %{k: "death", v: 13}, %{k: "ooo", v: 0}],
...>   & &1.k,
...>   & &1.v
...> )
%{"life" => 42, "death" => 13, "ooo" => 0}

Specs

index_of(Enumerable.t(), any()) :: non_neg_integer() | nil

Finds the index of a value inside an enumerable.

Examples

iex> Swiss.Enum.index_of([1, 2, 3, 4], 3)
2

iex> Swiss.Enum.index_of([1, 2, 3, 4], 1)
0

iex> Swiss.Enum.index_of([1, 2, 3, 4], 5)
nil

Specs

reduce_while_ok(Enumerable.t()) :: :ok | {:ok, any()} | any()

Reduces the given enumerable while its elements match :ok or {:ok, _}, halting otherwise. Returns the last iterated term.

Examples

iex> Swiss.Enum.reduce_while_ok([:ok, :ok, :ok])
:ok

iex> Swiss.Enum.reduce_while_ok([:ok, {:ok, 15}])
{:ok, 15}

iex> Swiss.Enum.reduce_while_ok([:ok, {:ok, 15}, {:error, :oh_no}])
{:error, :oh_no}

iex> Swiss.Enum.reduce_while_ok([])
:ok

Specs

thru(Enumerable.t(), function()) :: Enumerable.t()

Applies cb to all elements in enum, ignores the return and returns enum.

Examples

iex> Swiss.Enum.thru([1, 2, 3], fn a -> a + 1 end)
[1, 2, 3]