class Collection
extends
Map<K, V>export declare class Collection<K, V> extends Map<K, V>
A Map with additional utility methods. This is used throughout discord.js rather than Arrays for anything that has an ID, for significantly improved performance and ease-of-use.
Type Parameters
K
V
atindex: number) : V | undefined (
Identical to Array.at(). Returns the item at a given index, allowing for positive and negative integers. Negative integers count back from the last item in the collection.
cloneCollection<K, V> () :
Creates an identical shallow copy of this collection.
const newColl = someColl.clone();
static combineEntriesK
V
>(entries: Iterable<[K, V]>combine: (firstValue: V, secondValue: V, key: K) => V) : Collection<K, V> <
K
V
Creates a Collection from a list of entries.
Collection.combineEntries([["a", 1], ["b", 2], ["a", 2]], (x, y) => x + y);
// returns Collection { "a" => 3, "b" => 2 }
concatcollections: ReadonlyCollection<K, V>[]) : Collection<K, V> (
Combines this collection with others into a new collection. None of the source collections are modified.
const newColl = someColl.concat(someOtherColl, anotherColl, ohBoyAColl);
differenceT
>(other: ReadonlyCollection<K, T>) : Collection<K, T | V> <
T
The difference method returns a new structure containing items where the key is present in one of the original structures but not the other.
Identical to Map.forEach(), but returns the collection instead of undefined.
collection
.each(user => console.log(user.username))
.filter(user => user.bot)
.each(user => console.log(user.username));
Obtains the value of the given key if it exists, otherwise sets and returns the value provided by the default value generator.
collection.ensure(guildId, () => defaultGuildConfig);
equalscollection: ReadonlyCollection<K, V>) : boolean (
Checks if this collection shares identical items with another. This is different to checking for equality using equal-signs, because the collections may be different objects, but contain the same data.
Returns: Whether the collections have identical contents
everyK2 extends K
>(fn: (value: V, key: K, collection: this) => key is K2) : this is Collection<K2, V> <
K2 extends K
Checks if all items passes a test. Identical in behavior to Array.every().
collection.every(user => !user.bot);
filterK2 extends K
>(fn: (value: V, key: K, collection: this) => key is K2) : Collection<K2, V> <
K2 extends K
Identical to Array.filter(), but returns a Collection instead of an Array.
collection.filter(user => user.username === 'Bob');
Searches for a single item where the given function returns a truthy value. This behaves like Array.find(). All collections used in Discord.js are mapped using their id
property, and if you want to find by id you should use the get
method. See MDN for details.
collection.find(user => user.username === 'Bob');
Searches for the key of a single item where the given function returns a truthy value. This behaves like Array.findIndex(), but returns the key rather than the positional index.
collection.findKey(user => user.username === 'Bob');
flatMapT
>(fn: (value: V, key: K, collection: this) => Collection<K, T>) : Collection<K, T> <
T
Maps each item into a Collection, then joins the results into a single Collection. Identical in behavior to Array.flatMap().
collection.flatMap(guild => guild.members.cache);
hasAllkeys: K[]) : boolean (
Checks if all of the elements exist in the collection.
Returns: true
if all of the elements exist, false
if at least one does not exist.
hasAnykeys: K[]) : boolean (
Checks if any of the elements exist in the collection.
Returns: true
if any of the elements exist, false
if none exist.
intersectT
>(other: ReadonlyCollection<K, T>) : Collection<K, T> <
T
The intersect method returns a new structure containing items where the keys and values are present in both original structures.
keyAtindex: number) : K | undefined (
Identical to Array.at(). Returns the key at a given index, allowing for positive and negative integers. Negative integers count back from the last item in the collection.
Maps each item to another value into an array. Identical in behavior to Array.map().
collection.map(user => user.tag);
mapValuesT
>(fn: (value: V, key: K, collection: this) => T) : Collection<K, T> <
T
Maps each item to another value into a collection. Identical in behavior to Array.map().
collection.mapValues(user => user.tag);
mergeT
R
>(other: ReadonlyCollection<K, T>whenInSelf: (value: V, key: K) => Keep<R>whenInOther: (valueOther: T, key: K) => Keep<R>whenInBoth: (value: V, valueOther: T, key: K) => Keep<R>) : Collection<K, R> <
T
R
Merges two Collections together into a new Collection.
// Sums up the entries in two collections.
coll.merge(
other,
x => ({ keep: true, value: x }),
y => ({ keep: true, value: y }),
(x, y) => ({ keep: true, value: x + y }),
);
// Intersects two collections in a left-biased manner.
coll.merge(
other,
x => ({ keep: false }),
y => ({ keep: false }),
(x, _) => ({ keep: true, value: x }),
);
partitionK2 extends K
>(fn: (value: V, key: K, collection: this) => key is K2) : [Collection<K2, V>, Collection<Exclude<K, K2>, V>] <
K2 extends K
Partitions the collection into two collections where the first collection contains the items that passed and the second contains the items that failed.
const [big, small] = collection.partition(guild => guild.memberCount > 250);
Applies a function to produce a single value. Identical in behavior to Array.reduce().
collection.reduce((acc, guild) => acc + guild.memberCount, 0);
Identical to Array.reverse() but returns a Collection instead of an Array.
somefn: (value: V, key: K, collection: this) => unknown) : boolean (
Checks if there exists an item that passes a test. Identical in behavior to Array.some().
collection.some(user => user.discriminator === '0000');
sortcompareFunction?: Comparator<K, V>) : this (
The sort method sorts the items of a collection in place and returns it. The sort is not necessarily stable in Node 10 or older. The default sort order is according to string Unicode code points.
collection.sort((userA, userB) => userA.createdTimestamp - userB.createdTimestamp);
sortedcompareFunction?: Comparator<K, V>) : Collection<K, V> (
The sorted method sorts the items of a collection and returns it. The sort is not necessarily stable in Node 10 or older. The default sort order is according to string Unicode code points.
collection.sorted((userA, userB) => userA.createdTimestamp - userB.createdTimestamp);
subtractT
>(other: ReadonlyCollection<K, T>) : Collection<K, V> <
T
The subtract method returns a new structure containing items where the keys and values of the original structure are not present in the other.
sweepfn: (value: V, key: K, collection: this) => unknown) : number (
Removes items that satisfy the provided filter function.
Returns: The number of removed entries