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Proper way to declare custom exceptions in modern Python?
... with e.errors
Python 3 Update: In Python 3+, you can use this slightly more compact use of super():
class ValidationError(Exception):
def __init__(self, message, errors):
# Call the base class constructor with the parameters it needs
super().__init__(message)
# Now...
Standard alternative to GCC's ##__VA_ARGS__ trick?
...
I'm afraid I don't have a proof, nor am I anymore the right person to try to think one up. I did write half of GCC's preprocessor, but that was more than ten years ago, and I'd never have thought of the argument-counting trick below, even then.
– z...
Why is there no Constant feature in Java?
... final in Java seems to work like C++ const for value types, but more like a C++ non-const T& for reference types
– Mark K Cowan
Aug 18 '16 at 11:28
...
Counting the number of elements with the values of x in a vector
...> a[names(a)==435]
435
3
Or convert it into a data.frame if you're more comfortable working with that:
> as.data.frame(table(numbers))
numbers Freq
1 4 2
2 5 1
3 23 2
4 34 2
...
...
INNER JOIN ON vs WHERE clause
...NNER JOIN is ANSI syntax which you should use.
It is generally considered more readable, especially when you join lots of tables.
It can also be easily replaced with an OUTER JOIN whenever a need arises.
The WHERE syntax is more relational model oriented.
A result of two tables JOINed is a carte...
Binary Data in JSON String. Something better than Base64
...to be escaped so that it can be placed into a string element (i.e. zero or more Unicode chars in double quotes using backslash escapes) in JSON.
...
Should I mix AngularJS with a PHP framework? [closed]
...
It seems you may be more comfortable with developing in PHP you let this hold you back from utilizing the full potential with web applications.
It is indeed possible to have PHP render partials and whole views, but I would not recommend it.
To...
Why is it not advisable to have the database and web server on the same machine?
... of two servers (extra cost, dedicated network connection between the two, more maintenance, etc.), especially for a small application, where neither piece is using too much CPU or memory? Even with two servers, with one server compromised, an attacker could still do serious damage, either by delet...
What techniques can be used to speed up C++ compilation times?
... whatever, don't include the entire definition, forcing the compiler to do more work than it needs to. This can have a cascading effect, making this way slower than they need to be.
The I/O streams are particularly known for slowing down builds. If you need them in a header file, try #including <...
How do I check if an integer is even or odd? [closed]
...ve criticized my answer above stating that using x & 1 is "faster" or "more efficient". I do not believe this to be the case.
Out of curiosity, I created two trivial test case programs:
/* modulo.c */
#include <stdio.h>
int main(void)
{
int x;
for (x = 0; x < 10; x++)
...