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Java 256-bit AES Password-Based Encryption
I need to implement 256 bit AES encryption, but all the examples I have found online use a "KeyGenerator" to generate a 256 bit key, but I would like to use my own passkey. How can I create my own key? I have tried padding it out to 256 bits, but then I get an error saying that the key is too long. ...
What is the AppDelegate for and how do I know when to use it?
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I normally avoid the design approach implied by Andrew's use of the term "heart of your application". What I mean by this is that I think you should avoid lumping too many things in a central location -- good program design normall...
Which is better in python, del or delattr?
... (foo)
6 LOAD_CONST 1 ('bar')
9 CALL_FUNCTION 2
12 POP_TOP
This translates into the first running slightly faster (but it's not a huge difference – .15 μs on my machine).
Like the others have said, you should really...
How do the likely/unlikely macros in the Linux kernel work and what is their benefit?
I've been digging through some parts of the Linux kernel, and found calls like this:
10 Answers
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Move capture in lambda
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Generalized lambda capture in C++14
In C++14 we will have the so called generalized lambda capture. This enables move capture. The following will be legal code in C++14:
using namespace std;
// a unique_ptr is move-only
auto u = make_unique<some_type>( some, parameters );
// move...
In MySQL, how to copy the content of one table to another table within the same database?
...y the content of one table to another table within the same database. Basically, I would like to insert to a table from another table. Is there easy way of doing this?
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How to avoid explicit 'self' in Python?
...s leads to useful properties, such as: you can't add members which accidentally shadow non-members and thereby break code.
One extreme example: you can write a class without any knowledge of what base classes it might have, and always know whether you are accessing a member or not:
class A(some_fu...
Bootstrap 3 breakpoints and media queries
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Bootstrap 4 Media Queries
// Extra small devices (portrait phones, less than 576px)
// No media query since this is the default in Bootstrap
// Small devices (landscape phones, 576px and up)
@media (min-width: 576px) { ... }
// Medium devices (tablets, 768px a...
Using CMake, how do I get verbose output from CTest?
... which is using the Boost unit testing framework. This one binary contains all of the unit tests. I've added that binary to be run by CTest:
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Deep null checking, is there a better way?
...'d say
cake?.frosting?.berries?.loader
and the compiler would generate all the short-circuiting checks for you.
It didn't make the bar for C# 4. Perhaps for a hypothetical future version of the language.
Update (2014):
The ?. operator is now planned for the next Roslyn compiler release. Note ...