The challenge
Remove a exclamation mark from the end of string. For a beginner kata, you can assume that the input data is always a string, no need to verify it.
Examples
remove("Hi!") === "Hi"
remove("Hi!!!") === "Hi!!"
remove("!Hi") === "!Hi"
remove("!Hi!") === "!Hi"
remove("Hi! Hi!") === "Hi! Hi"
remove("Hi") === "Hi"
Test cases
test.describe("Basic Tests")
tests = [
#[input, [expected]],
["Hi!", "Hi"],
["Hi!!!","Hi!!"],
["!Hi", "!Hi"],
["!Hi!", "!Hi"],
["Hi! Hi!", "Hi! Hi"],
["Hi", "Hi"],
]
for inp, exp in tests:
test.assert_equals(remove(inp), exp)
The solution in Python
Option 1:
def remove(s):
if len(s):
return s[:len(s)-1] if s[::-1][0]=="!" else s
else:
return ""
Option 2 (using endswith):
def remove(s):
return s[:-1] if s.endswith('!') else s
Option 3 (simple):
def remove(s):
return s[:-1] if s and s[-1] == '!' else s
Option 4 (using regex):
def remove(s):
import re
return re.sub(r'!$', '', s)
I like option 4.
Its not pretty, but you know when you (re)look at the code, what exactly is being done and the intent.
Python 3.9 has a str.removesuffix() method:
def remove(s):
return s.removesuffix(‘!’)
https://www.python.org/dev/peps/pep-0616/
Thanks for the addition Wes!