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How does type Dynamic work and how to use it?
...t be questioned:
scala> val d = new DynImpl
d: DynImpl = DynImpl@24a519a2
scala> d.sum(1, 2, 3)
res89: Int = 6
scala> d.concat("a", "b", "c")
res90: String = abc
At the top of all, it is also possible to combine Dynamic with macros:
class DynImpl extends Dynamic {
import language.ex...
Is gcc 4.8 or earlier buggy about regular expressions?
...using sregex_token_iterator instead. And it works with g++.
string line="1a2b3c";
std::regex re("(\\d)");
std::vector<std::string> inVector{
std::sregex_token_iterator(line.begin(), line.end(), re, 1), {}
};
//prints all matches
for(int i=0; i<inVector.size(); ++i)
std::cout <&...
When to use the brace-enclosed initializer?
...T();. Otherwise it's either direct initialization syntax (i.e. T t(a0, a1, a2);), or sometimes default construction (T t; stream >> t; being the only case where I use that I think).
That doesn't mean that all braces are bad though, consider the previous example with fixes:
template<typena...
Heap vs Binary Search Tree (BST)
... CPU (4 cores / 8 threads, 2.90 GHz base, 8 MB cache), RAM: 2x Samsung M471A2K43BB1-CRC (2x 16GiB, 2400 Mbps), SSD: Samsung MZVLB512HAJQ-000L7 (512GB, 3,000 MB/s)
So clearly:
heap insert time is basically constant.
We can clearly see dynamic array resize points. Since we are averaging every 10k...
Are PDO prepared statements sufficient to prevent SQL injection?
...
Here is a great tutorial on PDO if you want to learn it. a2znotes.blogspot.in/2014/09/introduction-to-pdo.html
– RN Kushwaha
Sep 12 '14 at 17:08
11
...
How expensive is RTTI?
... }
template< class t1, class t2 >
void Fire( t1 a1, t2 a2 )
{
std::cout << "Fire\n";
}
fastdelegate::FastDelegateBase *mDelegate;
};
class Scaler
{
public:
Scaler( ZoomManager *aZoomManager ) :
mZoomManager( aZoomManager ) { }
...
What are the differences between the threading and multiprocessing modules?
...h CPU: Intel Core i7-7820HQ CPU (4 cores / 8 threads), RAM: 2x Samsung M471A2K43BB1-CRC (2x 16GiB), SSD: Samsung MZVLB512HAJQ-000L7 (3,000 MB/s).
Visualize which threads are running at a given time
This post https://rohanvarma.me/GIL/ taught me that you can run a callback whenever a thread is sche...
Grouping functions (tapply, by, aggregate) and the *apply family
..., b1 = 2, c1 = "Eeek"),
b = 3, c = "Yikes",
d = list(a2 = 1, b2 = list(a3 = "Hey", b3 = 5)))
# Result is named vector, coerced to character
rapply(l, myFun)
# Result is a nested list like l, with values altered
rapply(l, myFun, how="replace")
tapply - For when you...
What do 'real', 'user' and 'sys' mean in the output of time(1)?
...P51 laptop, Intel Core i7-7820HQ CPU (4 cores / 8 threads), 2x Samsung M471A2K43BB1-CRC RAM (2x 16GiB).
sleep
Non-busy sleep does not count in either user or sys, only real.
For example, a program that sleeps for a second:
#define _XOPEN_SOURCE 700
#include <stdlib.h>
#include <unistd.h...
Why all the Active Record hate? [closed]
...tions, even some logic if the DBMS allows it (MySQL is also grown-up now)
A2) very often, there is more than a data store: file system (blobs in database are not always a good decision...), legacy systems (imagine yourself "how" they will be accessed, many varieties possible.. but thats not the poi...