Introduction
In Python, it is often necessary to find the index of the first element in a list that satisfies a certain condition. This can be achieved using a list comprehension, enumerate(), and next(). In this challenge, you will be tasked with writing a function that finds the index of the first element in a list that satisfies a given testing function.
Find Matching Index
Write a function find_index(lst, fn) that takes a list lst and a testing function fn as arguments. The function should return the index of the first element in lst for which fn returns True.
def find_index(lst, fn):
return next(i for i, x in enumerate(lst) if fn(x))
find_index([1, 2, 3, 4], lambda n: n % 2 == 1) ## 0
Summary
In this challenge, you have learned how to find the index of the first element in a list that satisfies a given testing function. This can be achieved using a list comprehension, enumerate(), and next().