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Phantom types are useful for dealing with data, that has identical representations but isn't logically of the same type. A good example is dealing with currencies. If you work with currencies you absolutely never want to e.g. add two amounts of different currencies. What would the result currency o...

Some people recommend that you should apply various tests to a file before attempting to open it either to provide better diagnostics or avoid dealing with exceptions. For example, this method attempts to check if path corresponds to a readable file: public static File getValidatedFile(String path...

The default font formatting provided by the fillText and strokeText methods isn't very aesthetically appealing. Fortunately the canvas API provides properties for formatting text. Using the font property you can specify: font-style font-variant font-weight font-size / line-height font-family...

// Add observer let observer = NSNotificationCenter.defaultCenter().addObserverForName("nameOfTheNotification", object: nil, queue: nil) { (notification) in // Do operations with the notification in this block } // Remove observer NSNotificationCenter.defaultCenter().removeObser...

Run go test as normal, yet with the coverprofile flag. Then use go tool to view the results as HTML. go test -coverprofile=c.out go tool cover -html=c.out

Introduces a for loop or, in C++11 and later, a range-based for loop. // print 10 asterisks for (int i = 0; i < 10; i++) { putchar('*'); }

SQLite uses dynamic typing and ignores declared column types: > CREATE TABLE Test ( Col1 INTEGER, Col2 VARCHAR(2), -- length is ignored, too Col3 BLOB, Col4, -- no type required Col5 FLUFFY BUNNIES -- use whatever you want ); > ...

Dependencies can be added for specific product flavors in a similar fashion as build configurations. android { ... productFlavors { flavor1 { //... } flavor2 { //... } } } dependencies { flavor1Compile 'com.and...

Building project dependencies can sometimes be a tedious task. Instead of publishing a package version to NPM and installing the dependency to test the changes, use npm link. npm link creates a symlink so the latest code can be tested in a local environment. This makes testing global tools and proje...

You can use built-in functions to run PHP processes as forks. This is the most simple way to achieve parallel work if you don't need your threads to talk to each other. This allows you to put time intensive tasks (like uploading a file to another server or sending an email) to another thread so you...

A pointer to member of derived class can be converted to a pointer to member of base class using static_cast. The types pointed to must match. If the operand is a null pointer to member value, the result is also a null pointer to member value. Otherwise, the conversion is only valid if the member ...

Cross-site request forgery, also known as one-click attack or session riding and abbreviated as CSRF or XSRF, is a type of malicious exploit of a website where unauthorized commands are transmitted from a user that the website trusts. Learn more To enable CSRF protection, add the CsrfViewMid...

SELECT OBJECT_ID('MemOptTable1') AS MemOptTable1_ObjectID, OBJECT_ID('MemOptTable2') AS MemOptTable2_ObjectID GO SELECT name,description FROM sys.dm_os_loaded_modules WHERE name LIKE '%XTP%' GO Show all Memory Optimized Tables: SELECT name,type_desc,durability_desc,...

Returns a table with a rows containing the values that were actual (current) at the specified point in time in the past. SELECT * FROM Employee FOR SYSTEM_TIME AS OF '2016-08-06 08:32:37.91'

DECLARE CURSOR c_emp_to_be_raised(p_sal emp.sal%TYPE) IS SELECT * FROM emp WHERE sal < p_sal; BEGIN FOR cRowEmp IN c_emp_to_be_raised(1000) LOOP dbms_Output.Put_Line(cRowEmp .eName ||' ' ||cRowEmp.sal||'... should be raised ;)'); END LOOP; END; /

BEGIN FOR x IN (SELECT * FROM emp WHERE sal < 100) LOOP dbms_Output.Put_Line(x.eName ||' '||x.sal||'... should REALLY be raised :D'); END LOOP; END; / First advantage is there is no tedious declaration to do (think of this horrible "CURSOR" thing you had in previous ve...

This is a minimal possible XSLT transformation. It produces the string value of the source XML document. The output format is text. Source XML document: <t>Hello, World!</t> XSLT transformation: <xsl:stylesheet version="1.0" xmlns:xsl="http://www.w3.org/1999/XSL/T...

This example shows the base of almost any XSLT transformation and the most fundamental XSLT design pattern. Producing as output an XML document that is identical to the source XML document. Source XML document: <t>Hello, World!</t> XSLT transformation: <xsl:stylesheet version=&q...

Converts the specified string representation of a date and time to its DateTime equivalent using the specified format and culture-specific format information. The format of the string representation must match the specified format exactly. Convert a specific format string to equivalent DateTime Le...

To discover SQL Server's edition, product level and version number as well as the host machine name and the server type: SELECT SERVERPROPERTY('MachineName') AS Host, SERVERPROPERTY('InstanceName') AS Instance, DB_NAME() AS DatabaseContext, SERVERPROPERTY('Editio...