Returns the number of values stored under key
, or 0 if key
is not present.
Key
Iterates over key-value pairs. Unlike a normal map, the same key may appear several times.
Returns true if key
has any values
Iterates over all keys
Iteates over all keys and the count of values therein
Iterates over all values, regardless of key. Same value may re-appear if it's stored under different keys.
Returns true if the map is empty