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In STL maps, is it better to use map::insert than []?
...) will only create:
using std::cout; using std::endl;
typedef std::map<int, std::string> MyMap;
MyMap map;
// ...
std::pair<MyMap::iterator, bool> res = map.insert(MyMap::value_type(key,value));
if ( ! res.second ) {
cout << "key " << key << " already exists "
...
Insert auto increment primary key to existing table
... an primary key column but I was wondering if it's possible to insert data into the primary key column automatically (I already have 500 rows in DB and want to give them id but I don't want to do it manually). Any thoughts? Thanks a lot.
...
What's the best way to iterate over two or more containers simultaneously
...range: a function with one line of code is all I need. However, I would be interested if the performance of boost ranges is optimal as well.
– SebastianK
Nov 6 '14 at 15:45
...
How do I get the current line number?
...oo");
}
...
static void ShowMessage(string message,
[CallerLineNumber] int lineNumber = 0,
[CallerMemberName] string caller = null)
{
MessageBox.Show(message + " at line " + lineNumber + " (" + caller + ")");
}
This will display, for example:
Boo at line 39 (SomeMethodSomewhere)
Ther...
Why do I need to override the equals and hashCode methods in Java?
...therField() {
return anotherField;
}
@Override
public int hashCode() {
final int prime = 31;
int result = 1;
result = prime * result
+ ((importantField == null) ? 0 : importantField.hashCode());
return result;
}
@Override
...
How to document a string type in jsdoc with limited possible values
...on of the tooltip
* @param {String='up','down','left','right'} position pointer position
*/
setPosition(position='left'){
// YOUR OWN CODE
}
Oh yeah, I'm using ES6.
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Preferred Java way to ping an HTTP URL for availability
...way is using java.net.Socket.
public static boolean pingHost(String host, int port, int timeout) {
try (Socket socket = new Socket()) {
socket.connect(new InetSocketAddress(host, port), timeout);
return true;
} catch (IOException e) {
return false; // Either timeout ...
What does “%.*s” mean in printf?
...
You can use an asterisk (*) to pass the width specifier/precision to printf(), rather than hard coding it into the format string, i.e.
void f(const char *str, int str_len)
{
printf("%.*s\n", str_len, str);
}
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...
Compare two objects in Java with possible null values
...
This is what Java internal code uses (on other compare methods):
public static boolean compare(String str1, String str2) {
return (str1 == null ? str2 == null : str1.equals(str2));
}
...
What does the thread_local mean in C++11?
...o data that is seemingly global or static storage duration (from the viewpoint of the functions using it) but in actual fact, there is one copy per thread.
It adds to the current automatic (exists during a block/function), static (exists for the program duration) and dynamic (exists on the heap bet...