pythonerror-handlingproject

Error on the len() funtion for a palindrome project


I'm on chapter 2 of the book Impractical Python Projects and I'm working on the code that is supposed to go through a dictionary list, find the palindromes in the list, and print them out in a new list. Here's the code.

import load_dictionary

word_list= load_dictionary.load('2of4brif.txt')
pali_list= []

for word in word_list:
    if len(word) > 1 and word == word[::-1]:
        pali_list.append(word)

print("\nNumber of palindromes found = {}\n".format(len(pali_list)))
print(*pali_list, sep='\n')

I'm having problems wit the if statement with the len() function. When I try to run the code it keeps returning this error:

TypeError: object of type 'builtin_function_or_method' has no len()

I tried changing the name 'word' to something else, thinking that maybe it was the built-in funtion that was being talked about, but the result is the same for each word or letter that I tried to use

ADDITIONAL INFORMATION: 2of4brif.txt is a downloaded list of words provided for the project to be used for the search for palindromes.

Here's the code in load_dictionary:

load_dictionary.py


Solution

  • If the input file is just a list of words (one per line) then all you need is:

    pali_list = []
    
    def normalise(s: str) -> str:
        return s.strip().lower()
    
    def ispalindrome(s: str) -> bool:
        return len(s) > 1 and s == s[::-1]
    
    with open("2of4brif.txt") as words:
        for word in map(normalise, words):
            if ispalindrome(word):
                pali_list.append(word)
    
    print(f"\nNumber of palindromes found = {len(pali_list)}\n")
    print(*pali_list, sep="\n")