Iterates the given nested structure, calling the callback provided on each value. The key returned is an array of all the parent keys (and/or indices in a case of an array.)

The return value is self.

Parameters

• input: nested map/list/keyword to be walked through.
• fun: callback to be called on each {key, value} pair, where key is an array or deeply nested keys; e.g. on %{a: {b: 42}} will be called once, with tuple {[:a, :b], 42};

• opts: the options to be passed to the iteration

  • yield: [:all | :maps | :keywords | nil] what to yield; default: nil for yielding values only
  • structs: [:values | nil] when :values, the nested structs are considered leaves and returned to the iterator instead of being iterated through

Examples

iex> %{a: %{b: %{c: 42}}} |> Iteraptor.each(&IO.inspect/1)
{[:a, :b, :c], 42}
%{a: %{b: %{c: 42}}}

iex> %{a: %{b: %{c: 42}}} |> Iteraptor.each(&IO.inspect/1, yield: :all)
{[:a], %{b: %{c: 42}}}
{[:a, :b], %{c: 42}}
{[:a, :b, :c], 42}
%{a: %{b: %{c: 42}}}

Filters the deeply nested term, optionally calling the function on filtered entries.

The return value is the filtered term.

Parameters

• input: nested map/list/keyword to be filtered.
• fun: callback to be called on each {key, value} to filter entries.

• opts: the options to be passed to the iteration

  • yield: [:all | :maps | :keywords | what to yield; default: nil for yielding values only.

Examples

iex> %{a: %{b: 42, e: %{f: 3.14, c: 42}, d: %{c: 42}}, c: 42, d: 3.14}
...> |> Iteraptor.filter(fn {key, _} -> :c in key end, yield: :none)
%{a: %{e: %{c: 42}, d: %{c: 42}}, c: 42}

Build a nested structure out of a flatmap given, decomposing the names of keys and handling lists carefully.

%{"a.b.c": 42, "a.b.d.0": nil, "a.b.d.1": 42, "a.e.0": :f, "a.e.1": 42}
|> Iteraptor.from_flatmap
#⇒ %{a: %{b: %{c: 42, d: [nil, 42]}, e: [:f, 42]}}

Parameters

• input: flat map to be “expanded” to nested maps/lists,  
• transformer: the transformer function to be called on all the elements,  
• opts: additional options to be passed through.

Examples

iex> %{"a.b.c": 42} |> Iteraptor.from_flatmap
%{a: %{b: %{c: 42}}}

iex> %{"a.b.c": 42, "a.b.d": 42} |> Iteraptor.from_flatmap
%{a: %{b: %{c: 42, d: 42}}}

iex> %{"a.b.c": 42, "a.b.d": 42, "a.e": 42} |> Iteraptor.from_flatmap
%{a: %{b: %{c: 42, d: 42}, e: 42}}

iex> %{"0": 42, "1": 42} |> Iteraptor.from_flatmap
[42, 42]

iex> %{"1": :a1, "0": :a0, "2": :a2, "3": :a3, "4": :a4, "5": :a5,
...>   "6": :a6, "7": :a7, "8": :a8, "9": :a9, "10": :a10, "11": :a11}
...> |> Iteraptor.from_flatmap
[:a0, :a1, :a2, :a3, :a4, :a5, :a6, :a7, :a8, :a9, :a10, :a11]

iex> %{"0.a": 42, "0.b": 42} |> Iteraptor.from_flatmap
[%{a: 42, b: 42}]

iex> %{"a.0.0" => :b, "a.1" => 42, d: 42} |> Iteraptor.from_flatmap
%{a: [[:b], 42], d: 42}

iex> %{"a.b.c": 42, "a.b.d.0": nil, "a.b.d.1": 42, "a.e.0": :f, "a.e.1": 42}
...> |> Iteraptor.from_flatmap
%{a: %{b: %{c: 42, d: [nil, 42]}, e: [:f, 42]}}

iex> %{"0.a": 42, "0.b": 42} |> Iteraptor.from_flatmap(&IO.inspect/1)
{[0, :a], 42}
{[0, :b], 42}
[%{a: 42, b: 42}]

Produces a term ready-to-use with JSON interchange. Stringifies all keys and converts keywords to maps.

Examples

iex> Iteraptor.jsonify(%{foo: [1, 2, 3], bar: [baz: 42]})
%{"foo" => [1, 2, 3], "bar" => %{"baz" => 42}}

iex> Iteraptor.jsonify([foo: [:zzz], bar: :baz], values: true)
%{"foo" => ["zzz"], "bar" => "baz"}

Maps the given nested structure, calling the callback provided on each value. The key returned is a concatenated names of all the parent keys (and/or indices in a case of an array.)

The return value is the result of subsequent calls to the transformer given.

Parameters

• input: nested map/list/keyword to be mapped.
• fun: callback to be called on each {key, value} pair, where key is an array or deeply nested keys; e.g. on %{a: {b: 42}} will be called once, with tuple {[:a, :b], 42};

• opts: the options to be passed to the iteration

  • yield: [:all | :maps | :keywords | what to yield; default: nil for yielding values only.

Examples

iex> %{a: %{b: %{c: 42}}} |> Iteraptor.map(fn {_, v} -> v * 2 end)
%{a: %{b: %{c: 84}}}

iex> %{a: %{b: %{c: 42}}} |> Iteraptor.map(fn {k, _} -> Enum.join(k) end)
%{a: %{b: %{c: "abc"}}}

iex> %{a: %{b: %{c: 42}}}
...> |> Iteraptor.map(fn
...>      {[_], _} = self -> self
...>      {[_, _], _} -> "YAY"
...>    end, yield: :all)
%{a: %{b: "YAY"}}

Iteration with mapping and reducing. The function of arity 2, called back on each iteration with {k, v} pair and an accumulator is accepted.

The return value is the tuple, consisting of mapped input and the accumulator from the last call to the passed map-reducer.

Parameters

• input: nested map/list/keyword to be mapped.
• fun: callback to be called on each {key, value}, acc pair, where key is an array or deeply nested keys, value is the value and acc is the accumulator;

• opts: the options to be passed to the iteration

  • yield: [:all | :maps | :keywords | what to yield; default: nil for yielding values only.

Examples

iex> %{a: %{b: %{c: 42}}}
...> |> Iteraptor.map_reduce([], fn
...>      {k, %{} = v}, acc -> {{k, v}, [Enum.join(k, ".") | acc]}
...>      {k, v}, acc -> {{k, v * 2}, [Enum.join(k, ".") <> "=" | acc]}
...>    end, yield: :all)
{%{a: %{b: %{c: 84}}}, ["a.b.c=", "a.b", "a"]}

Iteration with reducing. The function of arity 2, called back on each iteration with {k, v} pair and an accumulator is accepted.

The return value is the result of the last call to the passed reducer function.

Parameters

• input: nested map/list/keyword to be mapped.
• fun: callback to be called on each {key, value}, acc pair, where key is an array or deeply nested keys, value is the value and acc is the accumulator;

• opts: the options to be passed to the iteration

  • yield: [:all | :maps | :keywords | what to yield; default: nil for yielding values only.

Examples

iex> %{a: %{b: %{c: 42}}}
...> |> Iteraptor.reduce([], fn {k, _}, acc ->
...>      [Enum.join(k, "_") | acc]
...>    end, yield: :all)
...> |> :lists.reverse()
["a", "a_b", "a_b_c"]

Build a flatmap out of nested structure, concatenating the names of keys.

%{a: %{b: %{c: 42, d: [nil, 42]}, e: [:f, 42]}} |> Iteraptor.to_flatmap
%{"a.b.c": 42, "a.b.d.0": nil, "a.b.d.1": 42, "a.e.0": :f, "a.e.1": 42}

Lists are handled gracefully, index is used as a key in resulting map.

Parameters

• input: nested map/list/keyword/struct to be flattened,  
• opts: the additional options to be passed through:     — delimiter (default: ".",) might be passed explicitly or configured with :iteraptor, :delimiter application setting.

Examples

iex> [:a, 42] |> Iteraptor.to_flatmap
%{0 => :a, 1 => 42}

iex> %{a: 42} |> Iteraptor.to_flatmap
%{a: 42}

iex> %{a: 42, b: 42} |> Iteraptor.to_flatmap
%{a: 42, b: 42}

iex> %{a: %{b: 42}, d: 42} |> Iteraptor.to_flatmap
%{"a.b" => 42, d: 42}

iex> %{a: [:b, 42], d: 42} |> Iteraptor.to_flatmap
%{"a.0" => :b, "a.1" => 42, d: 42}

iex> %{a: %{b: [:c, 42]}, d: 42} |> Iteraptor.to_flatmap
%{"a.b.0" => :c, "a.b.1" => 42, d: 42}

iex> %{a: %{b: 42}} |> Iteraptor.to_flatmap
%{"a.b" => 42}

iex> %{a: %{b: %{c: 42}}} |> Iteraptor.to_flatmap
%{"a.b.c" => 42}

iex> %{a: %{b: %{c: 42}}, d: 42} |> Iteraptor.to_flatmap
%{"a.b.c" => 42, d: 42}

iex> [a: [b: [c: 42]], d: 42] |> Iteraptor.to_flatmap
%{"a.b.c" => 42, d: 42}

iex> [a: [[:b], 42], d: 42] |> Iteraptor.to_flatmap
%{"a.0.0" => :b, "a.1" => 42, d: 42}

iex> %{a: %{b: %{c: 42, d: [nil, 42]}, e: [:f, 42]}} |> Iteraptor.to_flatmap
%{"a.b.c" => 42, "a.b.d.0" => nil, "a.b.d.1" => 42, "a.e.0" => :f, "a.e.1" => 42}

iex> %{a: %{b: %{c: 42, d: [nil, 42]}, e: [:f, 42]}}
...> |> Iteraptor.to_flatmap(delimiter: "_")
%{"a_b_c" => 42, "a_b_d_0" => nil, "a_b_d_1" => 42, "a_e_0" => :f, "a_e_1" => 42}