
  [;1m-spec is_map_key(Key, Map) -> boolean() when Key :: term(), Map :: map().[0m

[;;4mSince[0m:
  OTP 21.0

  Returns [;;4mtrue[0m if map [;;4mMap[0m contains [;;4mKey[0m and returns [;;4mfalse[0m if
  it does not contain the [;;4mKey[0m.

  The call fails with a [;;4m{badmap,Map}[0m exception if [;;4mMap[0m is not a
  map.

  Example:

    > Map = #{"42" => value}.
    #{"42" => value}
    > is_map_key("42",Map).
    true
    > is_map_key(value,Map).
    false

  Allowed in guard tests.
