Python .popleft()

The deque.popleft() method removes and returns the element from the left end (first element) of a deque object. A deque (double-ended queue) allows elements to be added or removed efficiently from both ends. Calling .popleft() on an empty deque raises an IndexError.

Syntax

deque.popleft()

Parameters:

The .popleft() method does not take any parameters.

Return value:

Returns the element removed from the left end of the deque.

Example

In this example, the first element is removed from the left end of a deque:

from collections import deque

# Create a deque with several elements
queue = deque(['apple', 'banana', 'cherry'])

# Remove the leftmost element
left_item = queue.popleft()
print("Removed element:", left_item)
print("Deque after popleft():", queue)

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The output of this code is:

Removed element: apple
Deque after popleft(): deque(['banana', 'cherry'])

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Codebyte Example

In this example, a deque is used to simulate a queue of customers. The first customer is served using .popleft():

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