Prelude.Map
Functions operating on maps.
Summary
| append_list(map, key, val) | Appends to an array value in a map, creating one if the key does not exist |
| atomify(map) | Turns all string map keys into atoms, leaving existing atoms alone (only top level) |
| deep_put(map, path, val) | Put an arbitrarily deep key into an existing map |
| del_in(object, path, item) | Remove a map key arbitrarily deep in a structure, similar to put_in |
| group_by(maps, groups) | Group a map by an array of keys |
| stringify(map) | Turns all atom map keys into strings, leaving existing strings alone (only top level) |
| switch(map) | Switch the keys with the values in a map |
| to_atom(x) | Converts strings to atoms, but leaves existing atoms alone |
Functions
Appends to an array value in a map, creating one if the key does not exist
Turns all string map keys into atoms, leaving existing atoms alone (only top level)
Put an arbitrarily deep key into an existing map
If a value already exists at that level, it is turned into a list
For example:
iex> map_deep_put(%{}, [:a, :b, :c], "0")
%{a: %{b: %{c: "0"}}}
iex> map_deep_put(%{a: %{b: %{c: "1"}}}, [:a, :b, :c, :d], "2")
%{a: %{b: %{c: [{:d, "2"}, "1"]}}}Remove a map key arbitrarily deep in a structure, similar to put_in
For example:
iex> a = {a: %{b: %{c: %{d: 1, e: 1}}}}
...> del_in(a, [:a, :b, :c], :d)
%{a: %{b: %{c: %{e: 1}}}}Group a map by an array of keys
Provide a list of maps, and a list of keys to group by. All maps must have all the group_by fields, other fields can vary.
For example:
iex> group_by(
...> [%{name: "stian", group: 1, cat: 2},
...> %{name: "per", group: 1, cat: 1}],
...> [:group, :cat])
%{1 =>
%{1 => %{cat: 1, group: 1, name: "per"},
2 => %{cat: 2, group: 1, name: "stian"}}}Turns all atom map keys into strings, leaving existing strings alone (only top level)
Switch the keys with the values in a map
Converts strings to atoms, but leaves existing atoms alone