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See unpacking in action with a practical example.
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Now that you've seen the basics
of how unpacking works,
0:00
let's look at a practical example.
0:03
Let's say that in the simple app you're
writing you wanna ask your users to
0:05
enter their full name.
0:08
Entering their full name together
is quicker for your users, but for
0:10
your purposes you'd rather have their
first names and last names separated.
0:12
With unpacking and multiple assignment
you can capture the first name and
0:17
last name entered by your
user into their own variables
0:20
in just one line of code,
let's take a look.
0:23
First we'll ask for the name.
0:26
The \n at the end of the input line simply
adds a new line to keep things neat in
0:39
the terminal.
0:43
Okay, so when this program is run, the
user will be prompted to enter their name.
0:45
Whatever the user enters is then
saved into the full name variable,
0:49
this will be a string value.
0:53
Strings can be split apart at different
delimiters using the string method, split.
0:55
Split is nothing more than a function
that has one parameter, the delimiter.
1:00
So when we call the split
method on a string,
1:04
we pass it whatever the delimiter
should be used to split that string.
1:06
The method then returns a list.
1:09
Each element in the list is
a piece of the broken up string.
1:11
So let’s split the full name variable.
1:15
We can safely assume that our users will
enter their full names with the space
1:17
between each word.
1:20
That space will be our delimiter.
1:22
I’ll call the split method on the input
string, and pass our argument,
1:24
a space character.
1:28
Before we move forward, let's print the
full name variable and run the program so
1:32
we can see the result of the split method.
1:36
Okay, it's prompted me
to enter my full name.
1:51
Yes, Ashley Boucher has been split
into a list with two elements.
1:58
The first element is the string 'Ashley',
2:02
and the second element
is the string 'Boucher'.
2:04
And lists, like all Python sequences,
can be unpacked.
2:07
So instead of assigning the input
string to a variable called full name,
2:11
let's take advantage of unpacking and
multiple assignment to get the two
2:15
elements of the list
into their own variables.
2:18
This change means that
the first element of the list,
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Ashley, will be assigned
to the variable first.
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And the second element of the list,
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Boucher, will be saved
to the variable last.
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Let's print these out, save, and run.
2:38
Clear this down here.
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Awesome we did it.
2:56
In one line of code we took a string,
split that string into a list, and
2:57
then unpacked that list into
two variables, first and last.
3:02
Now we're free to use these
variables separately.
3:06
This could be handy when saving your user
to a database, when printing a personal
3:08
message to your user, or
when alphabetizing a list of users.
3:12
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