The derivative of a type is the type of its type of one-hole contexts. This is the type that we would get if we make a type variable disappear in every possible point and sum the results.
As an example, we can take the triple type (a,a,a), and derive it, obtaining
data OneHoleContextsOfTriple = (a...
Functions can be seen as exponentials in our algebra. As we can see, if we take a type a with n instances and a type b with m instances, the type a -> b will have m to the power of n instances.
As an example, Bool -> Bool is isomorphic to (Bool,Bool), as 2*2 = 2².
iso1 :: (Bool -> Bool) -...
You can, of course, return lists from subs:
sub foo {
my @list1 = ( 1, 2, 3 );
my @list2 = ( 4, 5 );
return ( @list1, @list2 );
}
my @list = foo();
print @list; # 12345
But it is not the recommended way to do that unless you know what you are doing.
While th...
Usage
Sometimes, you could have to debug code in another PhpStorm project, you have to update the configuration.
PHP configuration
In php.ini, edit file and put xdebug.remote_autostart = 1
PhpStorm configuration
You also have to configure your IDE:
In the phpStorm configuration, Max. sim...
The most important consequence of the One Definition Rule is that non-inline functions with external linkage should only be defined once in a program, although they can be declared multiple times. Therefore, such functions should not be defined in headers, since a header can be included multiple tim...
Lets use the same code as above for this example.
#include <iostream>
void fail() {
int *p1;
int *p2(NULL);
int *p3 = p1;
if (p3) {
std::cout << *p2 << std::endl;
}
}
int main() {
fail();
}
First lets compile it
g++ -g -o main m...
A function template can be overloaded under the rules for non-template function overloading (same name, but different parameter types) and in addition to that, the overloading is valid if
The return type is different, or
The template parameter list is different, except for the naming of paramete...
This code sends a simple text-only email to [email protected]
EXEC msdb.dbo.sp_send_dbmail
@profile_name = 'The Profile Name',
@recipients = '[email protected]',
@body = 'This is a simple email sent from SQL Server.',
@subject = 'Simple email'
HTML content must be passed to sp_send_dbmail
SQL Server 2012
DECLARE @html VARCHAR(MAX);
SET @html = CONCAT
(
'<html><body>',
'<h1>Some Header Text</h1>',
'<p>Some paragraph text</p>',
'</body></html>'
)
SQL Server 2012
...
Returns an integer (int) value that indicates the difference between the soundex values of two character expressions.
Parameters:
character expression 1.
character expression 2.
Both parameters are alphanumeric expressions of character data.
The integer returned is the number of chars in th...
This is a very basic feature selection technique.
Its underlying idea is that if a feature is constant (i.e. it has 0 variance), then it cannot be used for finding any interesting patterns and can be removed from the dataset.
Consequently, a heuristic approach to feature elimination is to first re...
auto is used in the syntax for trailing return type:
auto main() -> int {}
which is equivalent to
int main() {}
Mostly useful combined with decltype to use parameters instead of std::declval<T>:
template <typename T1, typename T2>
auto Add(const T1& lhs, const T2& rh...
Whereas inside a Translation Unit, order of initialization of global variables is specified, order of initialization across Translation Units is unspecified.
So program with following files
foo.cpp
#include <iostream>
int dummyFoo = ((std::cout << "foo"), 0);
b...
A simple EntitySystem that processes a Family of entities not once per frame, but after a given interval. Entity processing logic should be placed in processEntity(Entity). For more info, please see IntervalIteratingSystem
In the below code example, the best usage for this is the physics world ...
As far as client-side JavaScript engines are concerned (those running inside a browser), there is no straightforward solution available for requesting content from sources other than the current domain. (By the way, this limitation does not exist in JavaScript-server tools such as Node JS.)
However...
Create Dynamic Web project, provide following information's as stated below
Project name : DemoSpringMVCProject
Target runtime : set as Apache Tomcat v7.0 server
Click on finish, successfully we have created dynamic web project.
Now we have to setup Spring-MVC framework :
Create web.xml...
SoundEffect.Play() plays the sound effect in a "fire-and-forget" fashion. The sound plays once and its lifetime is managed by the framework. You are not able to change the properties (volume, pan, pitch) of the sound during playback, loop it, position it in 3D or pause it.
You can hold a ...
Google Sheets is a spreadsheet application that runs on web browser. It doesn't require any installation or setup just a Google account and a modern web browser.
The first time a user runs a project's gradlew, it should be realized that it will do two key things:
Check to see if the version of the gradle used by the wrapper is already in ~/.gradle/wrapper/dists
If not, download the archive of the version from the internet
If you're in an environment t...
