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Quick Way to Implement Dictionary in C
...om scratch. I don't want it to be generic either -- something like string->int will do. But I do want it to be able to store an arbitrary number of items.
...
When should you use constexpr capability in C++11?
...
Suppose it does something a little more complicated.
constexpr int MeaningOfLife ( int a, int b ) { return a * b; }
const int meaningOfLife = MeaningOfLife( 6, 7 );
Now you have something that can be evaluated down to a constant while maintaining good readability and allowing slightly ...
What are C++ functors and their uses?
...which "look like" a function:
// this is a functor
struct add_x {
add_x(int val) : x(val) {} // Constructor
int operator()(int y) const { return x + y; }
private:
int x;
};
// Now you can use it like this:
add_x add42(42); // create an instance of the functor class
int i = add42(8); // and...
How can I disable ARC for a single file in a project?
...
For Xcode 4.3 the easier way might be: Edit/Refactor/Convert to objective-C ARC, then check off the files you don't want to be converted. I find this way the same as using the compiler flag above.
shar...
How do you create nested dict in Python?
...after lookup with missing key. no exception raised:\n', nest)
# Instead, convert back to normal dict...
nest_d = nest.to_dict(nest)
try:
print('converted to normal dict. Trying to lookup Wrong_key2')
nest_d['outer1']['wrong_key2']
except KeyError as e:
print('exception missing key', e)...
What is an “unwrapped value” in Swift?
...pe basically means that the variable can be nil.
Example:
var canBeNil : Int? = 4
canBeNil = nil
The question mark indicates the fact that canBeNil can be nil.
This would not work:
var cantBeNil : Int = 4
cantBeNil = nil // can't do this
To get the value from your variable if it is optional,...
Base64 Java encode and decode a string [duplicate]
...rt java.io.UnsupportedEncodingException;
import javax.xml.bind.DatatypeConverter;
public class EncodeString64 {
public static void main(String[] args) throws UnsupportedEncodingException {
String str = "77+9x6s=";
// encode data using BASE64
String encoded = Datatyp...
What's the point of const pointers?
I'm not talking about pointers to const values, but const pointers themselves.
17 Answers
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private final static attribute vs private final attribute
...new Test();
x.instanceVariable = 10;
y.instanceVariable = 20;
System.out.println(x.instanceVariable);
prints out 10: y.instanceVariable and x.instanceVariable are separate, because x and y refer to different objects.
You can refer to static members via references, although it's a bad idea to do s...
Backing beans (@ManagedBean) or CDI Beans (@Named)?
...
I've created beans.xml, converted @ManagedBean backing beans to @Named, and converted @ManagedProperty to @Inject. All is well with the world. However, if I change my @EJB annotations to @Inject, deployment fails (org.jboss.weld.exceptions.Deploymen...