f-strings

Lightning talk about f-strings. Presented at PyCascades 2018 in Vancouver.

Transcript

1. F-strings @mariatta
2. F-strings?
3. the new way to format strings
4. starting in Python 3.6
5. How?
6. How? "Hello, %s. You’re %s." % (name, age)
7. How? "Hello, {name}. You’re {age}.".format(name=name, age=age) "Hello, %s. You’re %s." % (name, age)
8. How? "Hello, {name}. You’re {age}.".format(name=name, age=age) f"Hello, {name}. You’re {age}." "Hello, %s. You’re %s." % (name, age)
9. Alternate usage
10. Alternate usage f"Hello, {name}. You’re {age}."
11. Alternate usage F"Hello, {name}. You’re {age}." f"Hello, {name}. You’re {age}."
12. Call a function >>> def to_uppercase(input): ... return input.upper() ... >>> name = “bart simpson” >>> print(f"Hi {to_uppercase(name)}!") Hi BART SIMPSON!
13. Format specifiers >>> pycascades = datetime(year=2018, month=1, day=22) >>> print(f"{pycascades:%b %d, %Y}") Jan 22, 2018
14. F-strings
15. Faster than str.format
16. Python 3.6
17. Free download www.python.org
18. Build from source https://docs.python.org/3.6/using/unix.html
19. Change your OS consider: MacOS X, Windows 10, fedora 26, ubuntu 17.10