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Difference between a Structure and a Union
...re that value.
union foo {
int a; // can't use both a and b at once
char b;
} foo;
struct bar {
int a; // can use both a and b simultaneously
char b;
} bar;
union foo x;
x.a = 3; // OK
x.b = 'c'; // NO! this affects the value of x.a!
struct bar y;
y.a = 3; // OK
y.b = 'c'; // OK
ed...
Does delete on a pointer to a subclass call the base class destructor?
...n this will happen when the containing object is destroyed.
class A
{
char *someHeapMemory;
public:
A() : someHeapMemory(new char[1000]) {}
~A() { delete[] someHeapMemory; }
};
class B
{
A* APtr;
public:
B() : APtr(new A()) {}
~B() { delete APtr; }
};
class C
{
A Amemb...
How do you print out a stack trace to the console/log in Cocoa?
...#import <UIKit/UIKit.h>
#import "AppDelegate.h"
int main(int argc, char *argv[])
{
@autoreleasepool {
int retval;
@try{
retval = UIApplicationMain(argc, argv, nil, NSStringFromClass([AppDelegate class]));
}
@catch (NSException *exception)
...
What's the difference between ASCII and Unicode?
...t their language (to support "é", in French, for example). Just using one extra bit doubled the size of the original ASCII table to map up to 256 characters (2^8 = 256 characters). And not 2^7 as before (128).
10000010 -> é (e with acute accent - 130)
10100000 -> á (a with acute accent - 16...
Mismatched anonymous define() module
... up if
You have an anonymous define ("modules that call define() with no string ID") in its own script tag (I assume actually they mean anywhere in global scope)
You have modules that have conflicting names
You use loader plugins or anonymous modules but don't use require.js's optimizer to bundle ...
Why does Git treat this text file as a binary file?
...ut need of a null (00h) byte for anything other than the nul char (the 'C' string terminator). Thus Git's text definition is that the content (well the first 1k bytes) should not have a null byte when utf-8 encoded. Try stackoverflow.com/questions/2241348/… for a fun read. My original comment ref...
Simple logical operators in Bash
... a variable is empty and -e $file to test if a file exists. There are also string equality operators: "$string1" == "$string2" (beware that the right-hand side is a pattern, e.g. [[ $foo == a* ]] tests if $foo starts with a while [[ $foo == "a*" ]] tests if $foo is exactly a*), and the familiar !, &...
iPhone get SSID without private library
...s: %@", __func__, interfaceNames);
NSDictionary *SSIDInfo;
for (NSString *interfaceName in interfaceNames) {
SSIDInfo = CFBridgingRelease(
CNCopyCurrentNetworkInfo((__bridge CFStringRef)interfaceName));
NSLog(@"%s: %@ => %@", __func__, interfaceName, SSIDInfo)...
How to get the text node of an element?
... possible iterations. Comparing two small numbers is better than comparing strings of various lengths (time and space considerations). The correct question to ask in this situation is "what kind / type of node do I have?", and not "what name do I have?" developer.mozilla.org/en-US/docs/Web/API/Node/...
Do I need to disable NSLog before release Application?
...BUG_MODE
#define DLog( s, ... ) NSLog( @"<%p %@:(%d)> %@", self, [[NSString stringWithUTF8String:__FILE__] lastPathComponent], __LINE__, [NSString stringWithFormat:(s), ##__VA_ARGS__] )
#else
#define DLog( s, ... )
#endif
Now instead of NSLog use DLog everywhere. When testing and debugging...