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Python Functional Python Functional Workhorses Map

Posted by Christian Loveridge
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Christian Loveridge
Python Web Development Techdegree Student 7,240 Points

Code Challenge: Map

For the code challenge: "Create a function named "reverse" which takes a single iterable as an argument, and returns a reversed version of that item."

I have entered this code into workspaces and the terminal--it works perfectly fine in both places. However, the code challenge keeps giving me a "Bummer! reverse didn't accept an argument."

For the life of me, I cannot figure out what's wrong here.

maps.py 
backwards = [
    'tac',
    'esuoheerT',
    'htenneK',
    [5, 4, 3, 2, 1],
]

def reverse(i):
    i = iter(i)
    idx = len(i)
    i2 = ""
    while idx:
        idx -= 1
        i2 += i[idx]
    return i2

1 Answer

Christian Loveridge
.a{fill-rule:evenodd;}techdegree
Christian Loveridge
Python Web Development Techdegree Student 7,240 Points

Figured it out, for anyone interested or also struggling--The code above WILL reverse strings and integers...however, something the test code is throwing at it is not compatible.

The correct solution was to use a slice, which steps backward through the iterable and returns the reverse:

def reverse(iterable):
     return iterable[::-1]