Set

The Set object stores unique values of any type, whether primitive values or object references. The Set is used as storage for all multi-value objects in this API: custom fields that store multiple values, issue links, issues in a project, and so on. You can access single values in the collection directly (see first(), last(), get(index)), use an iterator (see entries(), values()), or traverse with forEach(visitor) and find(predicate) methods. The workflow API is based on ECMAScript 5.1. This Set implementation mimics the functionality supported by the ES 6 Set interface.

Properties

Name	Type	Description
added	Set	The elements that are added to a field that stores multiple values in the current transaction. Only relevant when the Set represents a multi-valued property (field) of a persistent entity.
isChanged	boolean	When the Set represents a multi-valued property (field) of a persistent entity and the field is changed in the current transaction, this property is `true`.
removed	Set	The elements that are removed from a field that stores multiple values in the current transaction. Only relevant when the Set represents a multi-valued property (field) of a persistent entity.
size	number	The number of elements in a Set. Use thoughtfully, as the calculation for large collections (like `project.issues`) may be resource consumptive.

Methods

add

add(element)

Add an element to a Set. If the specified value is already present, a duplicate value is not added.

Parameters

Name	Type	Description
element	Object	The element to add to the Set.

clear

clear()

Remove all of the values from a Set.

delete

delete(element)

Remove an element from a Set. If the specified element is not present, nothing happens.

Parameters

Name	Type	Description
element	Object	The element to remove from the Set.

entries

entries()

Get an iterator for the entries in a Set. The same as values(). Use an iterator when you need to traverse over entries until a specific condition is met and modify the entries at the same time.

Return Value

Type	Description
Iterator .<Object>	An iterator for the collection of values.

Example

// We want to find first Critical among issue subtasks and assign it. const checkAndAssign = function(task) { if (task.fields.Priority.name === ctx.Priority.Critical.name) { task.fields.Assignee = ctx.currentUser; return true; } return false; }; const iter = issue.links['parent for'].entries(); let v = iter.next(); while (!v.done && !checkAndAssign(v.value)) { v = iter.next(); }

See Also

If you need to modify all of the elements in the Set, see forEach(visitor).
If you need to find an element that meets specific criteria, see find(predicate).

find

find(predicate)

Find the first element in a Set for which a predicate function returns true.

Parameters

Name	Type	Description
predicate	function	A function with one argument that returns either `true` or `false` for a given value in the Set.

Return Value

Type	Description
Object	The first value that returns `true` for the predicate function or undefined.

Example

issue.tags.find(function(tag) { return tag.name === 'release'; });

first

first()

Find the first object in a collection based on the order in which the elements were added to the Set.

Return Value

Type	Description
Object	The first object in a collection or `null` if the collection is empty.

forEach

forEach(visitor)

Apply a visitor function to each member of a collection.

Parameters

Name	Type	Description
visitor	function	The function to be applied to each member of the collection.

Example

issue.links['parent for'].forEach(function(child) { child.fields.Priority = issue.fields.Priority; });

get

get(index)

Find an element with a specific index position in a Set.

Parameters

Name	Type	Description
index	number	The ordinal index of the element to be returned from the Set.

Return Value

Type	Description
Object	An object at index position in a Set, or `null` if the Set contains fewer than (index + 1) elements.

has

has(element)

Checks a Set object to determine whether the specified element is present in the collection or not.

Parameters

Name	Type	Description
element	Object	The element to locate in the Set.

Return Value

Type	Description
boolean	If the element is found, returns `true`, otherwise, `false`.

isEmpty

isEmpty()

Checks a Set object to determine whether it is empty.

Return Value

Type	Description
boolean	If the Set is empty, returns `true`, otherwise, `false`.

isNotEmpty

isNotEmpty()

Checks a Set object to determine whether it is not empty.

Return Value

Type	Description
boolean	If the Set is not empty, returns `true`, otherwise, `false`.

last

last()

Find the last object in a collection based on the order in which the elements were added to the Set.

Return Value

Type	Description
Object	The last object in a collection or `null` if collection is empty.

map

map(visitor)

Transform each element in a Set and return the results as an array.

Available since 2025.3

Parameters

Name	Type	Description
visitor	function	A function called for each value with arguments `(value, index, set)`.

Return Value

Type	Description
Array.<*>	An array with the results of calling `visitor` on each element in insertion order.

Example

// Collect logins of all permitted users const logins = issue.permittedUsers.map((u) => u.login);

slice

slice(start, end)

Create a shallow copy of a portion of a Set as an array.

Available since 2025.3

Parameters

Name	Type	Description
start	number	Zero-based index at which to begin extraction. Negative values are treated as 0.
end	number	Zero-based index before which to end extraction. If omitted, extracts through the end.

Return Value

Type	Description
Array.<Object>	An array containing the extracted values in insertion order. Returns an empty array when the range is empty.

Example

// Get first 3 subtasks const firstThree = issue.links['parent for'].slice(0, 3);

values

values()

Get an iterator for the entries in a Set. The same as entries().

Return Value

Type	Description
Iterator .<Object>	An iterator for the collection of values.

See Also

For details, see entries().

10 September 2026