[Tut] Python next() - Printable Version

[Tut] Python next() - Printable Version

+- Sick Gaming (https://sickgaming.net)
+-- Forum: Programming (https://sickgaming.net/forum-76.html)
+--- Forum: Python (https://sickgaming.net/forum-83.html)
+--- Thread: [Tut] Python next() (/thread-98403.html)

[Tut] Python next() - xSicKxBot - 11-22-2020

Python next()

The

Code:
next(iterator)

function is one of Python’s built-in functions—so, you can use it without importing any library. It returns the next value from the

Code:
iterator

you pass as a required first argument. An optional second argument

Code:
default

returns the passed default value in case the iterator doesn’t provide a next value.

[Image: next_python-1-1024x576.jpg]

Syntax:

Code:
next(iterator, <default>)

Arguments:

iterator – the next element is retrieved from the
Code:
iterator
default (optional) – return value if iterator is exhausted (it doesn’t have a next element)

Related Tutorials:

Example 1: No Default Value

The following example shows the

Code:
next()

function in action—without using a default value in case the iterator is empty.

Code:
users = ['Alice', 'Bob', 'Carl', 'David'] # convert the list to an iterator
users_iterator = iter(users) x = next(users_iterator)
print(x)
# Output: 'Alice' x = next(users_iterator)
print(x)
# Output: 'Bob' x = next(users_iterator)
print(x)
# Output: 'Carl' x = next(users_iterator)
print(x)
# Output: 'David'

Each time you call

Code:
next(iterator)

, the iterator returns the next element in the iterator over the Python list

Code:
users

.

But what happens if you call the

Code:
next()

function once more on the now empty

Code:
users_iterator

object?

Code:
x = next(users_iterator)
print(x) '''
Traceback (most recent call last): File "C:\Users\xcent\Desktop\Finxter\Blog\HowToConvertBooleanToStringPython\code.py", line 22, in <module> x = next(users_iterator)
StopIteration '''

Python throws a

Code:
StopIteration

error.

Let’s learn how to fix this!

Example 2: With Default Value

Not providing Python a solution to the problem that the iterator may be empty is a common source of errors! You can fix the errors by passing the optional

Code:
default

argument:

Code:
x = next(users_iterator, 42)
print(x)
# 42

Now, you cannot crash the

Code:
next(...)

function anymore! Go ahead and try it…

Interactive Shell

The interactive code shell offers you a way to try your newly gained skill—understanding the

Code:
next()

function. Can you crash the script by changing the default value?

https://trinket.io/embed/python/dc149801a3

Exercise: Run the code in the interactive shell. Now, change the default value & run again!

Where to Go From Here?

Enough theory, let’s get some practice!

To become successful in coding, you need to get out there and solve real problems for real people. That’s how you can become a six-figure earner easily. And that’s how you polish the skills you really need in practice. After all, what’s the use of learning theory that nobody ever needs?

Practice projects is how you sharpen your saw in coding!

Do you want to become a code master by focusing on practical code projects that actually earn you money and solve problems for people?

Then become a Python freelance developer! It’s the best way of approaching the task of improving your Python skills—even if you are a complete beginner.

Join my free webinar “How to Build Your High-Income Skill Python” and watch how I grew my coding business online and how you can, too—from the comfort of your own home.

Join the free webinar now!

The post Python next() first appeared on Finxter.