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andai

age = 32

print(f"Age: {age}")

Thus concludes the lecture on f-strings.

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I find it funny and satisfying that Python has converged to it's own "printf", by which I mean print(f"").

It’s unclear what the big advantage is over `print("Age: "+age)`. It’s even more characters, in that specific example.

If age is a number, that won’t work.

Admittedly I’m not so familiar with Python; it does work in Java. In that case, introducing a less hazardous string concatenation operator would seem more universally useful.

In Python, that less hazardous string concatenation operator is an f-string.

I’m assuming you can only use it with string literals, hence it is less universally useful.

Nope, you can put expressions in them:

f'{a} = {functionThatReturnsAButHasSideEffects()}'

Toy examples aren’t the use case, rather multiple variables or expressions, perhaps with formatting (padding) as well.

f-string is shorter, less err prone, and faster for medium complexity or above.

  >>> age = 32
  >>> print("Age: " + age)
  Traceback (most recent call last):
    File "<stdin>", line 1, in <module>
  TypeError: can only concatenate str (not "int") to str

  >>> print("Age: " + str(age))
  Age: 32

As a side note, I always found it amusing that Python is dynamic but doesn't let you do this, while C# has static typing but lets you do string + number. (I looked into it a while back, I think it's because both are Object, so it does operator overloading on Object+Object and then checks the types...)

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