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What is The Rule of Three?
...in various contexts,
and we should understand what "copying an object" actually means.
Let us consider a simple example:
class person
{
std::string name;
int age;
public:
person(const std::string& name, int age) : name(name), age(age)
{
}
};
int main()
{
person a("Bjar...
About Android image and asset sizes
...dpi
0.75 | 1 | 1.33 | 1.5 | 2 | 3 | 4
Although you don't really need to worry about tvdpi unless you're developing specifically for Google TV or the original Nexus 7 -- but even Google recommends simply using hdpi assets.
What this means is if you're doing a 48dip image and plan to ...
Does SQLAlchemy have an equivalent of Django's get_or_create?
...
That's basically the way to do it, there is no shortcut readily available AFAIK.
You could generalize it ofcourse:
def get_or_create(session, model, defaults=None, **kwargs):
instance = session.query(model).filter_by(**kwargs).firs...
Ineligible Devices section appeared in Xcode 6.x.x
After installing Xcode 6 my devices moved to greyed-out section Ineligible Devices and I can't select them as deploy target:
...
How to make/get a multi size .ico file? [closed]
...
I had all the images already, delivered by the artist for mac. All I had to do was open one of them in Gimp, and the choose "Open as layers.." on the remaining ones. All layers are automatically created in the correct size, export ...
How to make the 'cut' command treat same sequental delimiters as one?
... characters to tab. For example: I came here looking for a way to automatically export my display: who am i | tr -s ' ()' '\t' | cut -f5
– Leo
Mar 28 '16 at 23:24
...
How much is the overhead of smart pointers compared to normal pointers in C++?
..._ptr always has memory overhead for reference counter, though it is very small.
std::unique_ptr has time overhead only during constructor (if it has to copy the provided deleter and/or null-initialize the pointer) and during destructor (to destroy the owned object).
std::shared_ptr has time overhe...
How do I convert a float number to a whole number in JavaScript?
I'd like to convert a float to a whole number in JavaScript. Actually, I'd like to know how to do BOTH of the standard conversions: by truncating and by rounding. And efficiently, not via converting to a string and parsing.
...
How to catch integer(0)?
...
If it's specifically zero length integers, then you want something like
is.integer0 <- function(x)
{
is.integer(x) && length(x) == 0L
}
Check it with:
is.integer0(integer(0)) #TRUE
is.integer0(0L) #FALSE
is.integer0(...
The shortest possible output from git log containing author and date
...ded as well.
5aed68e 17 hours ago you@me.com Shorten while loops
This is all of course in color, so it is easy to distinguish the various parts of a log line.
Also it is the default when typing git log because of the [format] section.
2014 UPDATE:
Since git now supports padding I have a nice amen...