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Can a recursive function be inline?
...
First, the inline specification on a function is just a hint. The compiler can (and often does) completely ignore the presence or absence of an inline qualifier. With that said, a compiler can inline a recursive function, much as it can unroll an infinite loop. It simply has to ...
Cannot use ref or out parameter in lambda expressions
... can be accessed after the method frame is no longer on the stack
Func<int> Example(int p1) {
return () => p1;
}
Another property of captured variables is that changes to the variable are also visible outside the lambda expression. For example the following prints 42
void Example2(in...
Can table columns with a Foreign Key be NULL?
...
Yes, you can enforce the constraint only when the value is not NULL. This can be easily tested with the following example:
CREATE DATABASE t;
USE t;
CREATE TABLE parent (id INT NOT NULL,
PRIMARY KEY (id)
) ENGINE=INNODB;
CREATE TABLE...
Round to 5 (or other number) in Python
...thon, but this works for me:
Python 2
def myround(x, base=5):
return int(base * round(float(x)/base))
Python3
def myround(x, base=5):
return base * round(x/base)
It is easy to see why the above works. You want to make sure that your number divided by 5 is an integer, correctly rounde...
What is the best way to find the users home directory in Java?
...\Application Data (CSIDL_LOCAL_APPDATA).
Sample JNA code:
public class PrintAppDataDir {
public static void main(String[] args) {
if (com.sun.jna.Platform.isWindows()) {
HWND hwndOwner = null;
int nFolder = Shell32.CSIDL_LOCAL_APPDATA;
HANDLE hToken...
Java: method to get position of a match in a String?
...
The family of methods that does this are:
int indexOf(String str)
indexOf(String str, int fromIndex)
int lastIndexOf(String str)
lastIndexOf(String str, int fromIndex)
Returns the index within this string of the first (or last) occurrence of the specified ...
What are some uses of template template parameters?
...he exact type explicitly.
which you can use like this:
f<std::vector, int>(v); // v is of type std::vector<int> using any allocator
or better yet, we can just use:
f(v); // everything is deduced, f can deal with a vector of any type!
UPDATE: Even this contrived example, while illu...
Getting View's coordinates relative to the root layout
...swers. One claims to be faster, and another claims to be easier.
private int getRelativeLeft(View myView) {
if (myView.getParent() == myView.getRootView())
return myView.getLeft();
else
return myView.getLeft() + getRelativeLeft((View) myView.getParent());
}
private int get...
Which, if any, C++ compilers do tail-recursion optimization?
... done for more than a decade), even for mutually recursive calls such as:
int bar(int, int);
int foo(int n, int acc) {
return (n == 0) ? acc : bar(n - 1, acc + 2);
}
int bar(int n, int acc) {
return (n == 0) ? acc : foo(n - 1, acc + 1);
}
Letting the compiler do the optimisation is stra...
Android, ListView IllegalStateException: “The content of the adapter has changed but ListView did no
...hers to refer.
My loader on the main screen loads the phone book contacts into my data sources in the background.
@Override
public Void loadInBackground() {
Log.v(TAG, "Init loadings contacts");
synchronized (SingleTonProvider.getInstance()) {
PhoneBookManager.p...