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pythonany

Return value of any()

I have a question about returning a value of the any function in Python.

Here is the code:

def check():
   for l in lines:
       ret = any(word in l for word in list)
       return ret

It only returns a bool, but I need the word which matched with the list.

For example:

If I have the string "In school they're eating for lunch a lot of unhealthy food" and the list ["lunch", "burger", "sushi"] then I would need the word "lunch".

Solution

  • In Python 3.8, the assignment expression can be used to capture the witness that causes any to return True.

    for l in lines:
    if any((x:=word) in l for word in list):
        return x

    If any returns True, it is because the value of word (assigned to x) caused word in l to be true. x and word are bound in different scopes: word in the scope of the generator expression, x in the scope where the generator expression is defined.