TypeError: endswith first arg must be str or a tuple of str, not bool

python python-3.x count boolean ends-with
Mohammed picture Mohammed · Oct 1, 2015 · Viewed 16.1k times · Source

I was trying to count the occurrences of words which end with several suffixes. I thought that endswith would accept an iterable; unfortunately, it did not. Below is the code snippet:

s = 'like go goes likes liked liked liking likes like'
lst = s.split()
suffixes = ['s', 'es', 'ies', 'ed', 'ing']

counter = 0
prompt = 'like'
for x in lst:
    if x.startswith(prompt) and x.endswith(any(suffix for suffix in suffixes)):
         counter += 1

The value of counter should be 4 at the end of the execution. This is the error message which is displayed:

TypeError: endswith first arg must be str or a tuple of str, not bool

How can I get the above code to work?

Answer

kasravnd picture kasravnd · Oct 1, 2015

The any function returns a bool value, but str.startswith requires a string or a tuple of strings.

You can just convert your list to a tuple and pass it to startswith:

x.endswith(tuple(suffixes))

Related questions

Count the uppercase letters in a string with Python

I am trying to figure out how I can count the uppercase letters in a string. I have only been able to count lowercase letters: def n_lower_chars(string): return sum(map(str.islower, string)) Example of what I …

Read More
Convert bytes to a string

I'm using this code to get standard output from an external program: >>> from subprocess import * >>> command_stdout = Popen(['ls', '-l'], stdout=PIPE).communicate()[0] The communicate() method returns an array of bytes: >>> …

Read More
Best way to convert string to bytes in Python 3?

There appear to be two different ways to convert a string to bytes, as seen in the answers to TypeError: 'str' does not support the buffer interface Which of these methods would be better or more Pythonic? Or is it …

Read More