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Logical XOR operator in C++?
...!= !B implements the proper XOR in that regard.
But if you care about the extra sequence point though, neither != nor bitwise ^ is the proper way to implement XOR. One possible way to do XOR(a, b) correctly might look as follows
a ? !b : b
This is actually as close as you can get to making a hom...
C pointer to array/array of pointers disambiguation
... Example:
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#define NUM_ELEM(ar) (sizeof(ar) / sizeof((ar)[0]))
int *
put_off(const int newrow[2])
{
static int mymatrix[3][2];
static int (*rowp)[2] = mymatrix;
int (* const border)[] = mymatrix + NUM_ELEM(mym...
How to track down a “double free or corruption” error
...debug it.
#include<stdio.h>
#include<stdlib.h>
int main()
{
char *x = malloc(100);
free(x);
free(x);
return 0;
}
[sand@PS-CNTOS-64-S11 testbox]$ vim t1.c
[sand@PS-CNTOS-64-S11 testbox]$ cc -g t1.c -o t1
[sand@PS-CNTOS-64-S11 testbox]$ ./t1
*** glibc detected *** ./t1: double free ...
Null coalescing in powershell
...alpha', 5, 0, '', @(), $null, $true, $false
$instances = $items -ne $null
[string]::Join(', ', ($instances | ForEach-Object -Process { $_.GetType() }))
# Result:
System.String, System.Int32, System.Int32, System.String, System.Object[],
System.Boolean, System.Boolean
-eq works similarly, which is...
Difference between Static and final?
...dard library classes are final, for example java.lang.System and java.lang.String. All methods in a final class are implicitly final.
A final method can't be overridden by subclasses. This is used to prevent unexpected behavior from a subclass altering a method that may be crucial to the function or...
Should I return a Collection or a Stream?
...ood example of this are the APIs in java.nio.file.Files:
static Stream<String> lines(path)
static List<String> readAllLines(path)
Not only does readAllLines have to hold the entire file contents in memory in order to store it into the result list, it also has to read the file to t...
What is the best Java email address validation method? [closed]
... email package is the easiest:
public static boolean isValidEmailAddress(String email) {
boolean result = true;
try {
InternetAddress emailAddr = new InternetAddress(email);
emailAddr.validate();
} catch (AddressException ex) {
result = false;
}
return result;
}
...
How do you round a float to two decimal places in jruby
...ason, see comments), so that is the better solution if you are looking for string output.
– Dylan Vander Berg
Aug 6 '17 at 4:33
...
Convert generic List/Enumerable to DataTable?
...agnostics;
public class MyData
{
public int A { get; set; }
public string B { get; set; }
public DateTime C { get; set; }
public decimal D { get; set; }
public string E { get; set; }
public int F { get; set; }
}
static class Program
{
static void RunTest(List<MyData&g...
How to configure socket connect timeout
... timeout.</param>
public static void Connect(this Socket socket, string host, int port, TimeSpan timeout)
{
AsyncConnect(socket, (s, a, o) => s.BeginConnect(host, port, a, o), timeout);
}
/// <summary>
/// Connects the specified socket.
/// </summar...