doesntHave method
If this map does not contains the given key
/value
pair.
Example:
Map<String, dynamic> map = {"name": "John", "age": 30};
print(map.doesntHave("gender", "male")); // true
print(map.doesntHave("gender", null)); // true
Implementation
bool doesntHave(String key, T value) => !has(key, value);