Your for-loop might be missing an else block (Python 3 )
Your for-loop might be missing an else block
There's a little-known construct in Python that can be quite useful: using else in combination with loops. That's right, for-loops and while-loops can be followed by an
else block! Let's look at how you can use the else block in combination with a for-loop.
When is this
else block executed?
else block is executed as soon as:
- Your for-loop is out of elements
- The expression in your
With this exception: when you exit the loop with a
break or a
return, the else block will be skipped.
When to use?
Whenever you find yourself using a flag inside a loop, e.g., a boolean variable like
found, you can probably use
In this crumb, we check if the letter 'Q' is in the variable
name using a loop. (Yes, I know, there's a better way!) Instead of using a flag like
found to print the fact that a 'Q' was not found, we use
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