f-strings

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

Transcript

1. F-strings @mariatta
   

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2. F-strings?
   

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3. the new way to format strings
   

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4. starting in Python 3.6
   

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5. How?
   

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6. How?
   "Hello, %s. You’re %s." % (name, age)
   

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7. How?
   "Hello, {name}. You’re {age}.".format(name=name, age=age)
   "Hello, %s. You’re %s." % (name, age)
   

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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)
   

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9. Alternate usage
   

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10. Alternate usage
    f"Hello, {name}. You’re {age}."
    

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11. Alternate usage
    F"Hello, {name}. You’re {age}."
    f"Hello, {name}. You’re {age}."
    

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12. Call a function
    >>> def to_uppercase(input):
    ... return input.upper()
    ...
    >>> name = “bart simpson”
    >>> print(f"Hi {to_uppercase(name)}!")
    Hi BART SIMPSON!
    

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13. Format specifiers
    >>> pycascades = datetime(year=2018, month=1, day=22)
    >>> print(f"{pycascades:%b %d, %Y}")
    Jan 22, 2018
    

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14. F-strings
    

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15. Faster than str.format
    

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16. Python 3.6
    

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17. Free download
    www.python.org
    

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18. Build from source
    https://docs.python.org/3.6/using/unix.html
    

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19. Change your OS
    consider: MacOS X, Windows 10, fedora 26, ubuntu 17.10
    

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