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When should I use require() and when to use define()?
...n that handles definitions of modules. Differs from
* require() in that a string for the module should be the first argument,
* and the function to execute after dependencies are loaded should
* return a value to define the module corresponding to the first argument's
* name.
*/
The define() ...
When should you use constexpr capability in C++11?
... pi = 3.1415f;
// Haven't you always wanted to do this?
// constexpr std::string awesome = "oh yeah!!!";
// UPDATE: sadly std::string lacks a constexpr ctor
struct A
{
static const int four = 4;
static const int five = 5;
constexpr int six = 6;
};
int main()
{
&A::four; // linker ...
How to wait for several Futures?
...Future { println("f1!");throw new RuntimeException; 1 }
def func2 : Future[String] = Future { Thread.sleep(2000);println("f2!");"f2" }
def func3 : Future[Double] = Future { Thread.sleep(2000);println("f3!");42.0 }
val f : Future[(Int,String,Double)] = {
for {
f1 <- func1.concurrently
f...
Set operations (union, intersection) on Swift array?
...let array1 = ["a", "b", "c"]
let array2 = ["a", "b", "d"]
let set1:Set<String> = Set(array1)
let set2:Set<String> = Set(array2)
Swift 3.0+ can do operations on sets as:
firstSet.union(secondSet)// Union of two sets
firstSet.intersection(secondSet)// Intersection of two sets
firstSet....
iOS UIImagePickerController result image orientation after upload
...ker: UIImagePickerController,
didFinishPickingMediaWithInfo info: [String : Any]){
let chosenImage = info[UIImagePickerControllerOriginalImage] as! UIImage
profileImg.contentMode = .scaleAspectFill
let fixOrientationImage=chosenImage.fixOrientation()
profileIm...
seek() function?
...
For strings, forget about using WHENCE: use f.seek(0) to position at beginning of file and f.seek(len(f)+1) to position at the end of file. Use open(file, "r+") to read/write anywhere in a file. If you use "a+" you'll only be ab...
LINQ to SQL - Left Outer Join with multiple join conditions
...ollows:
public static IEnumerable<Announcementboard> GetSiteContent(string pageName, DateTime date)
{
IEnumerable<Announcementboard> content = null;
IEnumerable<Announcementboard> addMoreContent = null;
try
{
content = from c in DB.Announcementb...
Read stream twice
...you can do like this:
public class StreamTest {
public static void main(String[] args) throws IOException {
byte[] bytes = new byte[] { 1, 2, 3, 4, 5, 6, 7, 8, 9 };
InputStream originalStream = new ByteArrayInputStream(bytes);
byte[] readBytes = getBytes(originalStream, 3);
prin...
Python how to write to a binary file?
...eorder='big'))
I.e., each single call to to_bytes in this case creates a string of length 1, with its characters arranged in big-endian order (which is trivial for length-1 strings), which represents the integer value byte. You can also shorten the last two lines into a single one:
newFile.write(...
'size_t' vs 'container::size_type'
...
For std::[w]string, std::[w]string::size_type is equal to std::allocator<T>::size_type, which is equal to the std::size_t. For other containers, it's some implementation defined unsigned integer type.
Sometimes it's useful to hav...