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Object reference not set to an instance of an object.Why doesn't .NET show which object is `null`?
... exception helper in Visual Studio 2017 see the end of this answer)
Consider this code:
String s = null;
Console.WriteLine(s.Length);
This will throw a NullReferenceException in the second line and you want to know why .NET doesn't tell you that it was s that was null when the exception was th...
Python __str__ versus __unicode__
...ould implement __str__() versus __unicode__() . I've seen classes override __unicode__() more frequently than __str__() but it doesn't appear to be consistent. Are there specific rules when it is better to implement one versus the other? Is it necessary/good practice to implement both?
...
Does const mean thread-safe in C++11?
...const is now the equivalent of Java's synchronized?
No. Not at all...
Consider the following overly simplified class representing a rectangle:
class rect {
int width = 0, height = 0;
public:
/*...*/
void set_size( int new_width, int new_height ) {
width = new_width;
hei...
Mercurial move changes to a new branch
... Mark's answer, moving around already pushed changesets generally is a bad idea, unless you work in a small team where you are able to communicate and enforce your history manipulation.
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impr...
Javascript web app and Java server, build all in Maven or use Grunt for web app?
We are doing a web application with AngularJS and we like the idea of using Bower for Dependency Management and Grunt for building, running tests etc. ( Yeoman )
...
memory_get_peak_usage() with “real usage”
...
@Niko, Why did you use memory_get_peak_usage instead of memory_get_usage ? Shouldn't we gc_disable() and use memory_get_usage to get a more accurate result?
– Pacerier
Jul 13 '13 at 7:34
...
Should I pass an std::function by const-reference?
... you have a function called "run this in the UI thread".
std::future<void> run_in_ui_thread( std::function<void()> )
which runs some code in the "ui" thread, then signals the future when done. (Useful in UI frameworks where the UI thread is where you are supposed to mess with UI elem...
How to declare a structure in a header that is to be used by multiple files in c?
...Struct ; /* Forward declaration */
struct MyStruct
{
/* etc. */
} ;
void doSomething(struct MyStruct * p) /* parameter */
{
struct MyStruct a ; /* variable */
/* etc */
}
While a typedef will enable you to write it without the struct keyword.
struct MyStructTag ; /* Forward declaration *...
Instance variables vs. class variables in Python
...guration. I wonder which of the following options would be better or more "idiomatic" Python.
4 Answers
...
Why does casting int to invalid enum value NOT throw exception?
... (int, short, byte, etc), and so it can actually have any value that is valid for those value types.
I personally am not a fan of the way this works, so I made a series of utility methods:
/// <summary>
/// Utility methods for enum values. This static type will fail to initialize
/// (throw...