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How does functools partial do what it does?
...e code more readable. re.search method's signature is:
search(pattern, string, flags=0)
By applying partial we can create multiple versions of the regular expression search to suit our requirements, so for example:
is_spaced_apart = partial(re.search, '[a-zA-Z]\s\=')
is_grouped_together = ...
How to Calculate Execution Time of a Code Snippet in C++
...without Boost (tested on macOS/iOS):
#include <chrono>
#include <string>
#include <iostream>
#include <math.h>
#include <unistd.h>
class NLTimerScoped {
private:
const std::chrono::steady_clock::time_point start;
const std::string name;
public:
NLTimerSco...
clearing a char array c
...he other hand, if you are choosing to view this as a C/C++ null terminated string, setting the first byte to 0 will effectively clear the string.
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If strings are immutable in .NET, then why does Substring take O(n) time?
Given that strings are immutable in .NET, I'm wondering why they have been designed such that string.Substring() takes O( substring.Length ) time, instead of O(1) ?
...
Using backticks around field names
...
I actually had someone edit the extra backticks out of one of my question once, which upset me, since this reason is the exact reason I surround every variable with them
– Brian Leishman
Apr 8 '15 at 16:33
...
Copy a file in a sane, safe and efficient way
...; src.rdbuf();
}
This is so simple and intuitive to read it is worth the extra cost. If we were doing it a lot, better to fall back on OS calls to the file system. I am sure boost has a copy file method in its filesystem class.
There is a C method for interacting with the file system:
#include ...
How do function pointers in C work?
...nted programming in C.
For example, the following lines is written in C:
String s1 = newString();
s1->set(s1, "hello");
Yes, the -> and the lack of a new operator is a dead give away, but it sure seems to imply that we're setting the text of some String class to be "hello".
By using funct...
sed or awk: delete n lines following a pattern
.../,$d' out.txt but it gives error saying : sed: -e expression #1, char 24: extra characters after command Thanks in advance.
– N mol
Aug 24 '13 at 2:37
8
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How can I reliably get an object's address when operator& is overloaded?
...long ) {
return reinterpret_cast<T*>(
&const_cast<char&>(reinterpret_cast<const volatile char &>(v)));
}
static inline T * f( T * v, int ) { return v; }
};
template<class T>
T * addressof( T & v ) {
return addressof_impl<T>::f( addr_i...
What is the C# equivalent of NaN or IsNumeric?
What is the most efficient way of testing an input string whether it contains a numeric value (or conversely Not A Number)? I guess I can use Double.Parse or a regex (see below) but I was wondering if there is some built in way to do this, such as javascript's NaN() or IsNumeric() (was that VB...