Method category index
dictionary enumerating (instance)
Store value as associated to the given key
Answer a new dictionary containing the key/value pairs for which aBlock returns true. aBlock only receives the value part of the pairs.
Rehash the receiver
Remove anAssociation's key from the dictionary
removeKey: anElement ifAbsent: aBlock
Remove the passed key from the dictionary, answer the result of evaluating aBlock if it is not found