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List Operation
1 Introduction
The List Operation activity can perform various actions on a list. See below for details on these actions.
2 Operation Types
A list operation action can execute any of the following types of operations.
2.1 Binary
These binary operations have as an input a list and either another list or an object. The resulting type depends on the type of the operation. All lists and objects must relate to the same entity.
| Operation | Description | Result Type |
|---|---|---|
| Union | The result is a combination of the elements of both parameters avoiding duplicates. | List |
| Intersect | The result is a list containing elements that appear in both parameters. | List |
| Subtract | The result is the first parameter with the element(s) of the second parameter removed. | List |
| Contains | Checks whether all elements of the second parameter are present in the first parameter. | Boolean |
| Equals | Checks whether the lists contain the same elements. | Boolean |
2.2 Sort
| Operation | Description | Result Type |
|---|---|---|
| Sort | Allows you to sort a list based on a number of attributes. The attributes are ordered to determine their priority while sorting. The input list remains in its original order while the sorted list is stored in the output variable. | List |
2.3 Member Inspections
These operations take a single list and a member (attribute or association) as input. The resulting type depends on the type of the operation.
| Operation | Description | Result Type |
|---|---|---|
| Find | Find the first object of which the member has the given value. Return an empty object if no matching object is found. | Object |
| Filter | Find all objects of which the member has the given value. Return an empty list if no matching object is found. | List |
2.4 Unary
These unary operations have a list as input and either an object or another list as a resulting type, depending on the operation.
| Operation | Description | Result Type |
|---|---|---|
| Head | The result is the first element of the list, or empty if the parameter contains zero elements or was initialized as empty. | Object |
| Tail | The result is a list containing all elements of the parameter except the first, or an empty list if the parameter contains zero elements or was initialized as empty. | List |
3 Output Properties
3.1 Name
Defines the name of the resulting List, Object or Boolean variable. The variable can be used by all activities that follow this activity.