Pop
Purpose
The pop task removes the last item from a non-empty job array variable and returns the removed item with a success finish state. It returns a failure finish state if the the job array variable has no elements.
Properties
| Incoming | Description | 
|---|---|
| Select Job Variable (required) | Select the job variable that will be modified. | 
| Outgoing | Description | 
|---|---|
| popped_item | The outgoing variable which contains the removed item. | 
Example
Assume a job variable named fruits with value ["apple","banana","orange"] and you want to remove the last element.
- In the pop task's properties dialog box, select fruitsfrom the Select Job Variables dropdown.
- Click UPDATE.
The pop task changes job variable fruits to have value ["apple","banana"], and it returns value orange in its outgoing variable popped_item.
Figure: Pop task

Push
Purpose
The push task adds an item to the end of a job array variable.
Properties
| Property | Description | 
|---|---|
| Select Job Variable (required) | Select the job variable from the dropdown list that will receive a new item at the end of its array value. | 
| Item Location (required) | Specify where to find the item to add. The item location may come from a "job" variable, a "static" value, or an earlier task's outgoing variable. | 
| Item (required) | If Item location is "static", the Value field becomes a text edit box; type the new value. If Item location is "job" or an earlier task, the Value field becomes a dropdown list; select one of the listed variables. | 
Example
Assume a job variable named fruits with value ["apple","banana","orange"] and you want to add pear as a fourth element in the array.
- In the push task properties dialog box, select fruitsfrom the Select Job Variables dropdown.
- Select Item Location static.
- Type pearin the Item text box.
- Click UPDATE.
The push task changes job variable fruits to have value ["apple","banana","orange", "pear"].
Figure: Push task

Shift
Purpose
The shift task removes the first item from a non-empty job array variable and returns the removed item with a success finish state. It returns a failure finish state if the the job array variable has no elements.
Properties
| Incoming | Description | 
|---|---|
| Select Job Variable (required) | Select the job variable that will be modified. | 
| Outgoing | Description | 
|---|---|
| shifted_item | The outgoing variable which contains the removed item. | 
Example
Assume a job variable named fruits with value ["apple","banana","orange"] and you want to remove the first element.
- In the pop task's properties dialog box, select fruitsfrom the Select Job Variables dropdown.
- Click UPDATE.
The shift task changes job variable fruits to have value ["banana","orange"], and it returns value apple in its outgoing variable shifted item.
Figure: Shift task
