3

I know of two ways to format a string:

  1. print 'Hi {}'.format(name)
  2. print 'Hi %s' % name

What are the relative dis/advantages of using either?

I also know both can efficiently handle multiple parameters like

print 'Hi %s you have %d cars' % (name, num_cars)

and

print 'Hi {0} and {1}'.format('Nick', 'Joe')
2
  • possible duplicate of Python string formatting: % vs. .format Commented Aug 27, 2013 at 21:40
  • There's yet another way to do this that may interest you which is using the string.Template class. I find the syntax more readable than plain % formating and most of format's. Since it's a class you can derive your own specialized subclasses as well. Commented Aug 27, 2013 at 22:05

2 Answers 2

1

There is not really any difference between the two string formatting solutions.

{} is usually referred to as "new-style" and %s is "old string formatting", but old style formatting isn't going away any time soon.

The new style formatting isn't supported everywhere yet though:

logger.debug("Message %s", 123)  # Works
logger.debug("Message {}", 123)  # Does not work. 

Nevertheless, I'd recommend using .format. It's more feature-complete, but there is not a huge difference anyway.

It's mostly a question of personal taste.

Sign up to request clarification or add additional context in comments.

Comments

0

I use the "old-style" so I can recursively build strings with strings. Consider...

'%s%s%s'

...this represents any possible string combination you can have. When I'm building an output string of N size inputs, the above lets me recursively go down each root and return up.

An example usage is my Search Query testing (Quality Assurance). Starting with %s I can make any possible query.

/.02

Comments

Start asking to get answers

Find the answer to your question by asking.

Ask question

Explore related questions

See similar questions with these tags.