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Python Comprehensions

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Conditional List Comprehension

8:14 with Rachel Johnson

We’ve just learned how to turn simple loops into a 1-line list comprehension. But what about loops that have conditional if/else blocks? List comprehension can handle that too!

The Syntax

# Condition affects the list
[expression for temp_var in iterable if condition]

# Condition affects the expression
[expression if condition else expression for temp_var in iterable]

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    But what about loops that have conditional if else blocks? 0:00
    List comprehensions can handle that too. 0:01
    There are two types of conditional list comprehension syntaxes, and it depends on 0:04
    whether the conditional effects the iterable, or if it affects the expression. 0:09
    When a conditional affects the iterable, 0:14
    the number of elements of the iterable might change based on the condition. 0:17
    Taking our welcome banner, for example, 0:22
    we might want to filter out any letter that isn't a vowel from the final string. 0:25

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