The next () function in Python

The next () function in Python returns the next element in the iterator. You can add a default value to return if iterable is already the last element.

Continuing with the topic of built-in functions in Python, the article will introduce you to the next () function with syntax, usage as well as specific examples. Invites you to read the track.

The next () function in Python returns the next element in the iterator. You can add a default value to return if iterable is already the last element.

The syntax of the next () function in Python:

 next(iterator, default)

Parameters of the next () function

The next () function has 2 parameters:

iterator : iterable object.
default : the default value will be returned if iterable is the last element.

Return value from next ()

The next () function returns the next element in the iterator
If the iterator runs out, the function returns the default value
If the iterator expires without a default value, the StopIteration exception will be raised.

Example 1: how does next () work?

 random = [5, 9, 'cat'] # chuyển list thành iterator randomIterator = iter(random) print(randomIterator) # Output: 5 print(next(randomIterator)) # Output: 9 print(next(randomIterator)) # Output: 'cat' print(next(randomIterator)) # Xảy ra lỗi # iterator hết print(next(randomIterator))

When you run the program, the output will be:

  5 9 cat Traceback (most recent call last): File "python", line 18, in StopIteration

In the above code, the list is an iterable object, and you can get the iterator from there using the built-in function iter () in Python.

Example 2: Iterator has the default value in next ()

 random = [5, 9] # chuyển list thành iterator randomIterator = iter(random) # Output: 5 print(next(randomIterator, '-1')) # Output: 9 print(next(randomIterator, '-1')) # randomIterator đã hết phần tử # Output: '-1' print(next(randomIterator, '-1')) print(next(randomIterator, '-1')) print(next(randomIterator, '-1'))

Return value:

 5 9 -1 -1 -1