52
votes
Accepted
Password checker in Python
Concept
Obligatory XKCD comic, before I begin:
Enforcing password strength by requiring human-unfriendly characters is no longer considered good practice. Nevertheless, I'll review the code as you ...
- 144k
39
votes
Verifying a person's age
The biggest problem I see here is that you are printing a warning message to System.out and then using a default value for something which sounds like an Exception.
...
- 59.1k
33
votes
Accepted
Accurate email syntax validation (no seriously)
"@"@example.com and "\ "@example.com both fail, but they are valid.
...
- 470
33
votes
Verifying IPv6 addresses
Python has a philosophy of "Batteries Included". Don't reinvent what's in the standard library!
In particular, this code is much more easily written if we take advantage of ...
- 72k
28
votes
Accepted
Verifying IPv6 addresses
You can change valid_characters to a string. 'ABCDEFabcdef:0123456789'.
You can use ...
- 42.7k
24
votes
Accurate email syntax validation (no seriously)
Said this in chat already, but @ succeeds even although it is not a valid email address. You should require at least 1 character in the local part and 1 character ...
- 22.3k
24
votes
Accurate email syntax validation (no seriously)
I personally find it hard to fault your code.
Actually I'm quite surprised about the absence of code.
Other than a few PEP8 errors there are three changes that I would recommend.
You remove both <...
- 42.7k
24
votes
Accepted
Program to check if a date is valid or not
Good work! While there is certainly room for improvement, it is good that you stuck it out and discovered a solution on your own.
...
- 3,456
22
votes
Accepted
Validating Yes/No answers in C++
You have a common bug that will send you into an infinite loop. :-)
When reading data (especially user input data) you must validate the read worked correctly. If the read fails and sets one of the ...
- 94.3k
20
votes
Validating Yes/No answers in C++
For a beginner, that's very good code.
There is one thing that almost all C++ programmers get wrong, and that's calling ::tolower with a ...
- 21.2k
19
votes
Checking if each char in a string is a decimal digit
In the cctype header, you have the std::isdigit(int) function. You can use this instead of your conditions that check if the ...
- 3,533
17
votes
"Suspicious comparison of integer references" while checking for a monotonically increasing sequence
You should only use == if you work with elementary data types (boolean, byte, char, short, int, long, float, long).
If you use <...
- 2,060
17
votes
Accurate email syntax validation (no seriously)
You seems to build your module to contain only validate as "public" function. You may want to enforce that by declaring ...
- 28.6k
17
votes
Accepted
Simple object validator
Instead of using regular expressions to manipulate the expression string I prefer to do expression manipulation. While this can be a little daunting at first it turns out to be fairly simple. It ...
- 805
16
votes
Accepted
Is date 18+ years old?
What about this:
function isDate18orMoreYearsOld(day, month, year) {
return new Date(year+18, month-1, day) <= new Date();
}
The ...
- 1,157
16
votes
Checking if each char in a string is a decimal digit
The other reviews have hit most of the important points, so I'll just provide a single line alternative that uses the C++11 std::regex_match. That function looks ...
- 65.3k
13
votes
Accepted
Input validation for a user
You could merge your two foreach loops using SelectMany in LINQ.
So instead of :
...
- 12.4k
12
votes
Accepted
Checking balanced parenthesis string
if(st.isEmpty())
return true;
else return false;
This can be simplified to return st.isEmpty();... Wait, that's not the ...
- 19.2k
12
votes
Accurate email syntax validation (no seriously)
The code that you've written is generally really good, but as you seem to have found parsing non-trivial strings starts to get kind of complicated, and has all sorts of room for nasty edge cases.
Your ...
- 840
12
votes
Accepted
Windows filepath and filename validation
For the if(filePath.Length >= 240) part, you can use the Path object.
It throws a ...
12
votes
Binary file validity in C++/C++11: checking a binary header
The most unforgivable fault with this function is that calling isValidBuffer() also erases the buffer! That completely violates the Principle of Least Surprise. If ...
- 144k
12
votes
Accepted
Password Validation in Python
You shouldn't use bare excepts, this is as it can prevent things like KeyboardInterrupt.
That's just bad.
...
- 42.7k
12
votes
Accepted
Checking some rules before a Telegram bot replies to a message
If you want to get rid of your nested code then you should make a function and use guard statements.
If we simplify your code a bit, we can have:
...
- 42.7k
12
votes
Accepted
Pythonic way for validating and categorizing user input
Don't print promiscuously. You've broken your problem down into several
small functions, which is a good general instinct. But you've undermined those
functions by polluting them with side effects -- ...
- 12.6k
11
votes
Input validation for a user
You can do this with more easily by manually creating a ValidationContext and then calling a Validator.TryValidateObject ...
- 16.9k
11
votes
Accepted
"Suspicious comparison of integer references" while checking for a monotonically increasing sequence
Integer[] vs int[]
This may be down to a 'personal preference' thing, but using primitive wrappers in an array instead of a <...
- 19.2k
11
votes
Validating integer or string input
You are clearly violating the Single Responsibility Principle (SRP) because the method is doing two things. You should use two methods where each validates one type only.
You will see also that for ...
- 50.3k
11
votes
Accepted
Enforcing string validity with the C# type system
Review
I find this is a very nice idea that I have borrow from you and while doing this I'd change a couple things to make it more mature and even more flexible.
...
- 44.2k
11
votes
Validate IP4 address
def validateIP(ip):
I would expect a name starting is (a useful hint that it returns a Boolean rather than some more complex ...
- 24.1k
11
votes
Repetitive validation of Console inputs
As you suggested, you have a lot of redundant code. And rightfully so you want to adhere to the DRY principle.
All these input methods have the same pattern internally..
...
- 13.9k
Only top scored, non community-wiki answers of a minimum length are eligible