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What is a Manifest in Scala and when do you need it?
...tic type of a collection. For example, what if you wanted to treat a List[String] differently from other types of a List:
def foo[T](x: List[T])(implicit m: Manifest[T]) = {
if (m <:< manifest[String])
println("Hey, this list is full of strings")
else
println("Non-string...
In Go's http package, how do I get the query string on a POST request?
...eal with POST request. How can I access and parse the content of the query string from the Request object ? I can't find the answer from the official documentation.
...
Write string to text file and ensure it always overwrites the existing content.
I have a string with a C# program that I want to write to a file and always overwrite the existing content. If the file isn't there, the program should create a new file instead of throwing an exception.
...
How do I set a column value to NULL in SQL Server Management Studio?
...value and clicking enter will not create a NULL value. If the column is a string datatype (varchar and the like), it will create an empty string. If the column is a numeric datatype (int and the like) it will pop up an Invalid Value error. And so on. NULL is the absence of a value, and is does no...
Is there any haskell function to concatenate list with separator?
..."?"]
"is there such a function ?"
unlines works similarly, only that the strings are imploded using the newline character and that a newline character is also added to the end. (This makes it useful for serializing text files, which must per POSIX standard end with a trailing newline)
...
NoClassDefFoundError: android.support.v7.internal.view.menu.MenuBuilder
...ns and change the app flow:
public static boolean isSamsung_4_2_2() {
String deviceMan = Build.MANUFACTURER;
String deviceRel = Build.VERSION.RELEASE;
return "samsung".equalsIgnoreCase(deviceMan) && deviceRel.startsWith("4.2.2");
}
Then in the activity's onCreate method:
if (...
How do I provide custom cast support for my class?
...c# but note that from that example, using the explicit method, if you do:
string name = "Test";
Role role = (Role) name;
Then everything is fine; however, if you use:
object name = "Test";
Role role = (Role) name;
You will now get an InvalidCastException because string cannot be cast to Role, ...
Simple example of threading in C++
...reate a function that you want the thread to execute, eg:
void task1(std::string msg)
{
std::cout << "task1 says: " << msg;
}
Now create the thread object that will ultimately invoke the function above like so:
std::thread t1(task1, "Hello");
(You need to #include <thread>...
Collections.emptyList() returns a List?
...arameter, and have your code behave as expected, like this:
public Person(String name) {
this(name,Collections.<String>emptyList());
}
Now when you're doing straight assignment, the compiler can figure out the generic type parameters for you. It's called type inference. For example, if ...
How do I change the text of a span element using JavaScript?
... then setting innerHTML might be acceptable:
// * Fine for hardcoded text strings like this one or strings you otherwise
// control.
// * Not OK for user-supplied input or strings you don't control unless
// you know what you are doing and have sanitized the string first.
document.getElementBy...