Strange out put on CamelCase vs camelCase Why ???

Question

I ran several test on words and sentences and my code worked yet when I ran the two versions of CamelCase mentioned above I received two different results.

CamelCase converted to all lowercase and no underscores... camelcase 🤔
camelCase converted to all lowercase as well but correct form as camel_case 👍

As I mentioned, I ran other test from
AbraCadAbra ( abra_cadabra 🤔) to
DicTionAry ( dic_tion_ary 👍) to AntiDisEstablishMenTarianIsm (
anti_dis_establish_men_tarian_ism
👍 )

I thought this was odd as this a SnakeCase code and yet when execution gave two different results ..
https://code.sololearn.com/c0Z2xn1iJ8We/?ref=app

Answer 1

BroFar the conditions that cause failure are:

1. The first letter is capitalized

and

2. Another letter in the word matches that first letter.

It will skip inserting the underscore because of the logic in line 4 where it checks for a match with the first letter.

Answer 2

Thanks Jay Matthews but why does that print statement have to be outside the for loop ?
It did correct both the CamelCase entry and the AbraCadAbra entry ..

print(x[0].lower(),end="")

understandable that x[0] comparison is not needed in the flow of the for loop.

Answer 3

Thank you Jay Matthews But still don't exactly understand the other oddities like why the no underscore in CamelCase and the second missing underscore in AbraCadAbra as _abra ..
The if condition was an 'and' not an 'or' so elif condition is isupper() boolean by itself.

Answer 4

Ah yes that makes totally sense.. Thanks Brian I see the error of my ways.

Answer 5

Saheed Kehinde please I understand that you are new here. Only add comments to threads that are of value to the quality of the threads.

Answer 6

You're welcome, BroFar. I find that it can be hard to find a bug when I am overconfident that my good intentions translated to a good implementation. It's a good example to explain to newbies why testing is necessary.

Answer 7

why the multiple print(end='')?
surely it would be more efficient to build a string then print at the end?

s = ''
for c in input():
if c.isupper():
s += f'_{c.lower()}'
else:
s += c
s = s.lstrip('_')
print(s)

or one liner:

print(''.join(['_'+c.lower() if c.isupper() else c for c in input()]).lstrip('_'))

and because it's Python, there's a library for this. 😁
https://code.sololearn.com/cqPOJTVZVV4I/?ref=app

Answer 8

But there is always the edge case of multiple consecutive uppercase that is always messed up...
example: IOError or HTTPRequest

Answer 9

It's PascalCase and cameCase

Answer 10

Hello