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if A vs if A is not None:
...back to database stuff. There's a big difference between NULL and an empty string. An empty string typically says "there's a value here, and that value is nothing at all". NULL says "this value hasn't been entered."
In each of those cases, you'd want to use if A is None. You're checking for a speci...
Convert integer to hexadecimal and back again
...Store integer 182
int intValue = 182;
// Convert integer 182 as a hex in a string variable
string hexValue = intValue.ToString("X");
// Convert the hex string back to the number
int intAgain = int.Parse(hexValue, System.Globalization.NumberStyles.HexNumber);
from http://www.geekpedia.com/KB8_How-d...
Why is it impossible to build a compiler that can determine if a C++ function will change the value
...int& val) {
cout << "Should I change value? [Y/N] >";
string reply;
cin >> reply;
if (reply == "Y") {
val = 42;
}
}
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Platform independent size_t Format specifiers in c?
...ng for? Browse other questions tagged c platform-independent size-t format-string format-specifiers or ask your own question.
What should a Multipart HTTP request with multiple files look like? [duplicate]
... just to avoid any confusion: notice that before each boundary string in the content there are two extra dashes --<boundary>. For the last line is --<boundary>--
– Radu Simionescu
Jun 14 '13 at 12:03
...
What does the restrict keyword mean in C++?
... saved, as mentioned by supercat and michael.
Consider for example:
void f(char *restrict p1, char *restrict p2, size_t size) {
for (size_t i = 0; i < size; i++) {
p1[i] = 4;
p2[i] = 9;
}
}
Because of restrict, a smart compiler (or human), could optimize that to:
mem...
Parse JSON String into a Particular Object Prototype in JavaScript
I know how to parse a JSON String and turn it into a JavaScript Object.
You can use JSON.parse() in modern browsers (and IE9+).
...
Convert to binary and keep leading zeros in Python
...most compact and direct option.
If you are putting the result in a larger string, use an formatted string literal (3.6+) or use str.format() and put the second argument for the format() function after the colon of the placeholder {:..}:
>>> value = 14
>>> f'The produced output, i...
How much size “Null” value takes in SQL Server
...
The following link claims that if the column is variable length, i.e. varchar then NULL takes 0 bytes (plus 1 byte is used to flag whether value is NULL or not):
How does SQL Server really store NULL-s
The above link, as well as the below link, claim that for fixed length columns, i.e. char(10...
Best way to strip punctuation from a string
...om an efficiency perspective, you're not going to beat
s.translate(None, string.punctuation)
For higher versions of Python use the following code:
s.translate(str.maketrans('', '', string.punctuation))
It's performing raw string operations in C with a lookup table - there's not much that will...