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Idrees Richard
166 PointsHi All,What is actually the purpose of the .format () command? I did some researching online and cant seem to understand
I'm not really sure why we actually need to use the .format(books[0])? rather than just printing out books[0]?
Thanks!
2 Answers
![Alex Koumparos](https://uploads.teamtreehouse.com/production/profile-photos/8418842/micro_IMG_1256__cropped_and_reduced_res_.jpg)
Alex Koumparos
Python Development Techdegree Student 36,887 PointsHi Anas,
There are two basic ways of combining some string literal (i.e., hard coded text) and some computed or stored value (e.g., something in a variable):
The first, format()
is used for string interpolation. This allows us to inject some code into a string and have it evaluated at runtime. For example:
my_variable = "world"
print("hello, {}".format(my_variable))
In most cases it is functionally equivalent to the second, string concatenation, using the +
operator:
my_variable = "world"
print("hello, " + my_variable)
and which one you'd use depends on personal preference or house style.
Later on, you'll learn some neat ways that you can use interpolation with tuples and dictionaries that you can't easily replicate with concatenation.
Hope that helps
Cheers
Alex
![Idrees Richard](https://secure.gravatar.com/avatar/6c422edc1a37753f8a1ff26dd6e649a6?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Idrees Richard
166 PointsThanks Alex!
Grigorij Schleifer
10,365 PointsGrigorij Schleifer
10,365 PointsHey Alex, very nice answer!!! I see a typo in the first print statement
though ![:smile: :smile:](https://image-proxy-cdn.teamtreehouse.com/7834ff468822a2940e57bd253e8d466c4aa54bf9/68747470733a2f2f7374617469632e7465616d74726565686f7573652e636f6d2f696d616765732f656d6f6a692f756e69636f64652f31663630342e706e67)