Preview Queue Element

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Returns the element at the front of the queue without removing the element from the queue.

If the queue becomes invalid because the queue reference is released, this node stops waiting and returns an error.

Note To return and remove the element from the queue, use Dequeue Element instead.

Inputs/Outputs

A reference to a queue.

The number of milliseconds that the node waits for an element to become available in the queue if the queue is empty.

If an element becomes available in the queue during the wait, the node removes and returns the element and does not time out.

Default value: -1 — The node never times out.

Error conditions that occur before this node runs.

Unlike most nodes, this node runs normally even if an error occurs before this node runs.

Default value: no error

Reference to the queue.

A copy of the element at the front of the queue.

The data type of this output changes to match the data type of the queue elements.

A Boolean value that indicates whether an element became available in the queue before the node timed out or if an error occurred.

True	An element did not become available before the node timed out or this node generated an error.
False	An element did become available before the node timed out or an error occurred before this node executed.

The node produces this output according to standard error behavior.

This node can return the following error codes.

1122	The reference became invalid while the node was waiting for it.

Note This is not a comprehensive list of errors this node can return.