Collections/A

STATUS: RECOMMENDATION. NOT STANDARDS TRACK

Lookup Table

del(key) this

• Deletes an item for a key.
• Returns the mutated collection.
• For ordered collections, accepts a beginning key and an ending key, deleting all items in that range of keys excluding the ending key.
• Implemented in terms of remove.

set(key, value) this

• Adds or overwrites an item for a key.
• Returns the mutated collection.
• Implemented in terms of insert.

cut(key, value_opt) Value

• Deletes an item for a key.
• If no item has the given key and no default value is provided, throws a KeyError.
• Returns the corresponding value, or the default value.
• Implemented in terms of get and del.

has(key, eq_opt, hash_opt) Boolean

• Returns whether key is among items.

put(key, value) Value

• Adds an item for a key.
• returns the mutated collection.
• In an ordered collection, reserves the right to change the keys of some other items to make room for the new item by shifting later items right.
• Throws a key error if there is already an item with that key and it cannot be moved to a different key.
• Implemented in terms of set and has.

get(key, value_opt) Value

• Returns a value for the given key.
• If there is no value for the given key and no default value is provided, throws a KeyError.
• Implemented in terms of retrieve and has.

getset(key, value) Value

• If there is no value for the given key, sets the value for the key to the given value.
• Returns the value for the given key.
• Implemented in terms of get and set.

keys() Set of Key

values() Array of Value

items() Array of [Key, Value] pairs

Lookup Set

insert(item, eq_opt, hash_opt) this

• Adds or overwrites a value.
• Returns the mutated collection.
• Defaults to an implementation in terms of find and set.

retrieve(item, eq_opt, hash_opt) Item

• Returns the contained value that is naturally equivalent to a given value.
• Throws a value error if none exists.
• Defaults to an implementation in terms of find and get.

remove(item, eq_opt, hash_opt) this

• Removes a value.
• Throws a value error if the value isn't in the collection.
• Returns the mutated collection.
• Defaults to an implementation in terms of find and del.

discard(item, eq_opt, hash_opt) this

• Removes a value if it exists.
• Returns the mutated collection.
• Implemented in terms of has and remove.

find(item, eq_opt, hash_opt) Item

• Returns the key for a given value.
• Accepts an optional equivalence relation to override the default of eq.