CommonX

v0.0.5

CommonX v0.0.5 MapX View Source

Some map extensions.

Link to this section Summary

Functions

atomize(map)

Transform the keys of a given map to atoms

atomize!(map)

Transform the keys of a given map to atoms

delete(map, key)

Deletes the entry in map for a specific key

fetch(map, key)

Fetches the value for a specific key in the given map. If map contains the given key with value value, then {:ok, value} is returned. If map doesn't contain key, :error is returned. Inlined by the compiler

get(map, key, default \\ nil)

Gets the value for a specific key in map

merge(map1, map2, fun)

Merges two maps into one, resolving conflicts through the given fun. All keys in map2 will be added to map1. The given function will be invoked when there are duplicate keys; its arguments are key (the duplicate key), value1 (the value of key in map1), and value2 (the value of key in map2). The value returned by fun is used as the value under key in the resulting map

new(enumerable, transform, struct \\ nil)

Creates a map from an enumerable via the given transformation function. Duplicated keys are removed; the latest one prevails

stringify(map)

Transform the keys of a given map to atoms

Link to this section Functions

Link to this function

atomize(map) View Source 
atomize(%{optional(String.t()) => any()}) :: %{optional(atom()) => any()}

Transform the keys of a given map to atoms.

Examples 

iex> MapX.atomize(%{a: 5})
%{a: 5}
iex> MapX.atomize(%{"a" => 5})
%{a: 5}
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atomize!(map) View Source 
atomize!(%{optional(String.t()) => any()}) :: %{optional(atom()) => any()}

Transform the keys of a given map to atoms.

Examples 

iex> MapX.atomize!(%{a: 5})
%{a: 5}
iex> MapX.atomize!(%{"a" => 5})
%{a: 5}
iex> MapX.atomize!(%{"non existing" => 5})
** (ArgumentError) argument error
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delete(map, key) View Source 
delete(map(), atom()) :: map()

Deletes the entry in map for a specific key.

If the key does not exist, returns map unchanged.

Inlined by the compiler.

Examples 

iex> MapX.delete(%{a: 1, b: 2}, :a)
%{b: 2}

iex> MapX.delete(%{"a" => 1, "b" => 2}, :a)
%{"b" => 2}

iex> MapX.delete(%{b: 2}, :a)
%{b: 2}
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fetch(map, key) View Source 
fetch(map(), atom()) :: {:ok, Map.value()} | :error

Fetches the value for a specific key in the given map. If map contains the given key with value value, then {:ok, value} is returned. If map doesn't contain key, :error is returned. Inlined by the compiler.

Examples 

iex> MapX.fetch(%{a: 1}, :a)
{:ok, 1}
iex> MapX.fetch(%{"a" => 1}, :a)
{:ok, 1}
iex> MapX.fetch(%{a: 1}, :b)
:error
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get(map, key, default \\ nil) View Source 
get(map(), atom(), Map.value()) :: Map.value()

Gets the value for a specific key in map.

If key is present in map with value value, then value is returned. Otherwise, default is returned (which is nil unless specified otherwise).

Examples 

iex> MapX.get(%{}, :a)
nil

iex> MapX.get(%{a: 1}, :a)
1

iex> MapX.get(%{"a" => 1}, :a)
1

iex> MapX.get(%{a: 1}, :b)
nil

iex> MapX.get(%{a: 1}, :b, 3)
3
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merge(map1, map2, fun) View Source 
merge(
  map(),
  map(),
  (Map.key(), Map.value(), Map.value() -> {:ok, Map.value()} | {:error, any()})
) :: {:ok, map()} | {:error, any()}

Merges two maps into one, resolving conflicts through the given fun. All keys in map2 will be added to map1. The given function will be invoked when there are duplicate keys; its arguments are key (the duplicate key), value1 (the value of key in map1), and value2 (the value of key in map2). The value returned by fun is used as the value under key in the resulting map.

Examples 

iex> MapX.merge(%{a: 1, b: 2}, %{a: 3, d: 4}, fn _k, v1, v2 ->
...>   {:ok, v1 + v2}
...> end)
{:ok, %{a: 4, b: 2, d: 4}}
````
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new(enumerable, transform, struct \\ nil) View Source 
new(
  Enumerable.t(),
  (term() -> {:ok, Map.key(), Map.value()} | {:error, term()}),
  module()
) :: map()

Creates a map from an enumerable via the given transformation function. Duplicated keys are removed; the latest one prevails.

Returning :skip will skip to the next value.

Examples 

iex> MapX.new([:a, :b], fn x -> {:ok, x, x} end)
{:ok, %{a: :a, b: :b}}
iex> MapX.new(1..5, &if(rem(&1, 2) == 0, do: :skip, else: {:ok, &1, &1}))
{:ok, %{1 => 1, 3 => 3, 5 => 5}}
Link to this function

stringify(map) View Source 
stringify(%{optional(atom()) => any()}) :: %{optional(String.t()) => any()}

Transform the keys of a given map to atoms.

Examples 

iex> MapX.stringify(%{a: 5})
%{"a" => 5}
iex> MapX.stringify(%{"a" => 5})
%{"a" => 5}