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What's the difference between passing by reference vs. passing by value?
...to it, I'll change the caller's variable itself, not e.g. whatever it is pointing to if it's a pointer.
This is now considered bad practice (as an implicit dependency). As such, virtually all newer languages are exclusively, or almost exclusively pass-by-value. Pass-by-reference is now chiefly use...
Guid is all 0's (zeros)?
...
Does it compile into the same IL as default(S) or are there any subtleties I'm missing?
– configurator
Nov 2 '11 at 19:02
...
Sequence-zip function for c++11?
...gt;
#include <vector>
#include <list>
#include <string>
int main() {
std::vector<int> a {4, 5, 6};
double b[] = {7, 8, 9};
std::list<std::string> c {"a", "b", "c"};
for (auto tup : boost::combine(a, b, c, a)) { // <---
int x, w;
do...
When to use “new” and when not to, in C++? [duplicate]
...ed when it goes out of scope. Some examples of this are:
void foo()
{
Point p = Point(0,0);
} // p is now destroyed.
for (...)
{
Point p = Point(0,0);
} // p is destroyed after each loop
Some people will say that the use of new decides whether your object is on the heap or the stack, but tha...
How can you do paging with NHibernate?
...
ICriteria has a SetFirstResult(int i) method, which indicates the index of the first item that you wish to get (basically the first data row in your page).
It also has a SetMaxResults(int i) method, which indicates the number of rows you wish to get (i.e...
How to randomly select rows in SQL?
...* FROM Table1
WHERE (ABS(CAST(
(BINARY_CHECKSUM
(keycol1, NEWID())) as int))
% 100) < 10
https://msdn.microsoft.com/en-us/library/cc441928.aspx
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...
Calculate the number of business days between two dates?
...wer. Especially in the real world situation, when you have to examine time intervals of several months.
See my code, with comments, below.
/// <summary>
/// Calculates number of business days, taking into account:
/// - weekends (Saturdays and Sundays)
/// - bank holidays in...
How to access command line parameters?
...econd iterated element.
An easy way to deal with the result of args is to convert it to a Vec:
use std::env;
fn main() {
let args: Vec<_> = env::args().collect();
if args.len() > 1 {
println!("The first argument is {}", args[1]);
}
}
You can use the whole standard i...
Cannot use ref or out parameter in lambda expressions
... can be accessed after the method frame is no longer on the stack
Func<int> Example(int p1) {
return () => p1;
}
Another property of captured variables is that changes to the variable are also visible outside the lambda expression. For example the following prints 42
void Example2(in...
Is there a string math evaluator in .NET?
...gests the builtin DataTable.Compute-"trick". Here it is.
double result = Convert.ToDouble(new DataTable().Compute("1 + 2 * 7", null));
The following arithmetic operators are supported in expressions:
+ (addition)
- (subtraction)
* (multiplication)
/ (division)
% (modulus)
More informations: D...