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Purpose of Unions in C and C++
...sn't force the standard to declare it as undefined behaviour - reinterpret_cast has exactly the same endian issues, but has implementation defined behaviour.
– JoeG
Feb 22 '10 at 11:42
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Rails 3 - can't install pg gem
...g= 'PATH_TO_YOUR_PG_CONFIG'
If you are not sure where your pg_config is, and assuming you are on Linux or Mac, you can run the following command:
which pg_config
Your pg-config can be in different locations depending on how you installed postgres.
...
When do you use the “this” keyword? [closed]
...e (struct) value.
To invoke an extension method on the current instance
To cast itself to another type
To chain constructors defined in the same class
You can avoid the first usage by not having member and local variables with the same name in scope, for example by following common naming conventi...
Difference between Arrays.asList(array) and new ArrayList(Arrays.asList(array))
...other interface. See the wrapper pattern article. | Where do you need to upcast? I'd suggest to use List<Integer> for your variable types (or method arguments etc.). This makes your code more generic and you can easily switch to another List implementation as needed, without having to rewrite ...
Python glob multiple filetypes
....glob in python to get a list of multiple file types such as .txt, .mdown, and .markdown? Right now I have something like this:
...
Programmatically find the number of cores on a machine
...;sysinfo);
int numCPU = sysinfo.dwNumberOfProcessors;
Linux, Solaris, AIX and Mac OS X >=10.4 (i.e. Tiger onwards)
int numCPU = sysconf(_SC_NPROCESSORS_ONLN);
FreeBSD, MacOS X, NetBSD, OpenBSD, etc.
int mib[4];
int numCPU;
std::size_t len = sizeof(numCPU);
/* set the mib for hw.ncpu */
mib[...
What is the exact problem with multiple inheritance?
...g part of the problem, if one does not need to allow identity-preserving upcasts and downcasts among all of the types from which an instance is derived or for which it is substitutable. Given X:B; Y:B; and Z:X,Y; assume someZ is an instance of Z. With virtual inheritance, (B)(X)someZ and (B)(Y)som...
What does multicore assembly language look like?
...that's needed is software support for each thread to set up its own tables and messaging queues. The OS uses those to do the actual multi-threaded scheduling.
As far as the actual assembly is concerned, as Nicholas wrote, there's no difference between the assemblies for a single threaded or multi ...
Should switch statements always contain a default clause?
...akes appropriate action for unhandled values, in case an invalid value was cast to the enum type. So this may work best for simple cases where you can return within the enum case rather than break.
enum SomeEnum
{
ENUM_1,
ENUM_2,
// More ENUM values may be added in future
};
int foo(So...
How to create Drawable from resource
...
As of API version 21 this method is deprecated and you should be replaced by: Drawable drawable = ResourcesCompat.getDrawable(getResources(), page.getImageId(), null);
– Boren
Apr 14 '15 at 23:07
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