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Is there a range class in C++11 for use with range based for loops?
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The C++ standard library does not have one, but Boost.Range has boost::counting_range, which certainly qualifies. You could also use boost::irange, which is a bit more focused in scope.
C++20's range library will allow you to do this ...
What are the best practices for using a GUID as a primary key, specifically regarding performance?
...have an application that uses GUID as the Primary Key in almost all tables and I have read that there are issues about performance when using GUID as Primary Key. Honestly, I haven't seen any problem, but I'm about to start a new application and I still want to use the GUIDs as the Primary Keys, but...
Can I set enum start value in Java?
... just labels for integers.
Java enums are implemented more like classes - and they can even have multiple attributes.
public enum Ids {
OPEN(100), CLOSE(200);
private final int id;
Ids(int id) { this.id = id; }
public int getValue() { return id; }
}
The big difference is that th...
PHP String to Float
...1,5h tracking down an issue caused by different locales causing (float) to convert on the first server to "," and on the second to ","
– Dr. Gianluigi Zane Zanettini
Jan 22 '16 at 15:36
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Why sizeof int is wrong, while sizeof(int) is right?
...that sizeof is an operator used for calculating the size of any datatype and expression, and when the operand is an expression, the parentheses can be omitted.
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parseInt vs unary plus, when to use which?
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The unary + on the other hand will return NaN if the entire string is non-convertible to a number.
parseInt('2a',10) === 2; //true
parseFloat('2a') === 2; //true
isNaN(+'2a'); //true
As seen in the comment of @Alex K., parseInt and parseFloat will parse by character. This means ...
What do the python file extensions, .pyc .pyd .pyo stand for?
...mode, without a console; executed with pythonw.exe
.pyx - Cython src to be converted to C/C++
.pyd - Python script made as a Windows DLL
.pxd - Cython script which is equivalent to a C/C++ header
.pxi - MyPy stub
.pyi - Stub file (PEP 484)
.pyz - Python script archive (PEP 441); this is a script con...
Comparing two collections for equality irrespective of the order of items in them
...g answers, since it takes nulls into account, implements IEqualityComparer and has some efficiency and edge case checks. plus, it's Microsoft :)
public class MultiSetComparer<T> : IEqualityComparer<IEnumerable<T>>
{
private readonly IEqualityComparer<T> m_comparer;
p...
How to increment a pointer address and pointer's value?
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First, the ++ operator takes precedence over the * operator, and the () operators take precedence over everything else.
Second, the ++number operator is the same as the number++ operator if you're not assigning them to anything. The difference is number++ returns number and then incre...
Difference between private, public, and protected inheritance
...g "next:".
There are three accessors that I'm aware of: public, protected and private.
Let:
class Base {
public:
int publicMember;
protected:
int protectedMember;
private:
int privateMember;
};
Everything that is aware of Base is also aware that Base contai...