Regex to delete characters from String that end with 'e', except for 2-3 letter words [clo-CodePudding

I am trying to create a regex expression in Python that deletes the letters 'e' in a word except for in cases where the word is 2 letters long. For example,

Become = Becom, Bee = Be, We = We, Be = Be

How is this possible? I am new to RegEx so any pointers would be appreciated.

CodePudding user response：

You don't have to use regex. Keep untouched the 2 first characters and replace 'e' starting the third characters.

lst = ['Become', 'Bee', 'We', 'Be']
for word in lst:
    new_word = word[:2]   word[2:].replace('e', '')
    print(f'{word:10} -> {new_word}')

Output:

Become     -> Becom
Bee        -> Be
We         -> We
Be         -> Be

CodePudding user response：

Without Regex you can solve it like so:

words = ["Become", "Bee", "We", "Be"]

for i, word in enumerate(words):
    if len(word) > 2 and word[-1] == "e":
        words[i] = word[:-1]
print(words)

And the output will be:

["Becom", "Be", "We", "Be"]

CodePudding user response：

As @Eladtopaz mentioned, you can check

while len(my_word) > 2 and my_word.endswith('e'):
    my_word = my_word[:-1]

.endwith because I see the first exapmple that only removes the last 'e', but in the other hand as you wrote in the question, you should check

if len(my_word) > 2 and 'e' in my_word:
    my_word = my_word.replace('e', '')

CodePudding user response：

for regex solutions you can do:

(.*[a-zA-Z]){3}= 3 letters (lower or Upper)

e$ = end with e

import re

test=['be','welcome','bee','eNd','enDeDe']

for word in test:
    y= re.sub(r"(.*[a-zA-Z]){3}e$",word[:-1],word)
    print(f"{word} => {y}")

Result:

be => be
welcome => welcom
bee => bee
eNd => eNd
enDeDe => enDeD

CodePudding user response：

You can use this pattern: (?=[a-zA-Z]{3,})([a-zA-Z] )e$

import re

list_of_words = ["Become", "Bee", "We", "Be"]
pattern = "(?=[a-zA-Z]{3,})([a-zA-Z] )e$"

print([re.sub(pattern, "\\1", x) for x in list_of_words])

Output:

['Becom', 'Be', 'We', 'Be']

CodePudding user response：

You could do it in a list comprehension by dropping the last character of the word using a conditional subscript:

words = ["Become", "Bee", "We", "Be"]

words = [w[:-w[2:].endswith('e') or None] for w in words]

print(words)
['Becom', 'Be', 'We', 'Be']