Tutorial by Examples: ch

Often you need to change the way a set of data is structured and manipulate certain values. In the example below we got a collection of books with an attached discount amount. But we much rather have a list of books with a price that's already discounted. $books = [ ['title' => 'The Pragma...

use-fixtures allows to wrap each deftest in namespace with code that runs before and after test. It can be used for fixtures or stubbing. Fixtures are just functions that take test function and run it with other necessary steps (before/after, wrap). (ns myapp.test (require [clojure.test :refer ...

We can use the :: syntax to dispatch on the type of an argument. describe(n::Integer) = "integer $n" describe(n::AbstractFloat) = "floating point $n" Usage: julia> describe(10) "integer 10" julia> describe(1.0) "floating point 1.0" Unlike m...

In Vue.js, every component instance has its own isolated scope, which means that if a parent component has a child component - the child component has its own isolated scope and the parent component has its own isolated scope. For any medium to large size app, following best practices conventions p...

The switch statement can also be used to attempt casting into different types: func checkType(_ value: Any) -> String { switch value { // The `is` operator can be used to check a type case is Double: return "value is a Double" // The `as` operator will ...

Search everywhere Double Shift Find Windows / Linux: Ctrl + F OS X / macOS: Cmd + F Find next F3 Find previous Shift + F3 Replace Windows / Linux: Ctrl + R OS X / macOS: Cmd + R Find in path Windows / Linux: Ctrl + Shift + F OS X / macOS: Cmd + Shift + F Replace in path Windows / Lin...

Simple Single Port RAM with one address for read/write operations. module ram_single #( parameter DATA_WIDTH=8, //width of data bus parameter ADDR_WIDTH=8 //width of addresses buses )( input [(DATA_WIDTH-1):0] data, //data to be written input [(ADDR_WIDTH-1):0] ad...

If logic of generic class or method requires checking equality of values having generic type, use EqualityComparer<TType>.Default property: public void Foo<TBar>(TBar arg1, TBar arg2) { var comparer = EqualityComparer<TBar>.Default; if (comparer.Equals(arg1,arg2) {...

XML <Galaxy> <Light>sun</Light> <Device>satellite</Device> <Sensor>human</Sensor> <Name>Milky Way</Name> </Galaxy> XPATH /Galaxy/*[local-name()='Light' or local-name()='Device' or local-name()='Sensor'] or //*[...

XML <Data> <BioLight> <name>Firefly</name> <model>Insect</model> </BioLight> <ArtificialLight> <name>Fire</name> <model>Natural element</model> <source>flint<...

XML <College> <FootBall> <Members>20</Members> <Coach>Archie Theron</Coach> <Name>Wild cats</Name> <StarFootballer>David Perry</StarFootballer> </FootBall> <Academics> ...

XML <College> <FootBall> <Members>20</Members> <Coach>Archie Theron</Coach> <Name>Wild cats</Name> <StarPlayer>David Perry</StarPlayer> </FootBall> <VolleyBall> <Me...

XML <Galaxy> <Light>sun</Light> <Device>satellite</Device> <Sensor>human</Sensor> <Name>Milky Way</Name> </Galaxy> XPATH /Galaxy/*[lower-case(local-name())="light"] or //*[lower-case(local-name())=&qu...

XML <Galaxy> <name>Milky Way</name> <CelestialObject name="Earth" type="planet"/> <CelestialObject name="Sun" type="star"/> </Galaxy> XPATH /Galaxy/*[contains(@name,'Ear')] or //*[contains(@name,'Ear...

XML <Galaxy> <name>Milky Way</name> <CelestialObject name="Earth" type="planet"/> <CelestialObject name="Sun" type="star"/> </Galaxy> XPATH /Galaxy/*[contains(lower-case(@name),'ear')] or //*[contain...

XML <Galaxy> <name>Milky Way</name> <CelestialObject name="Earth" type="planet"/> <CelestialObject name="Sun" type="star"/> </Galaxy> XPATH /Galaxy/*[starts-with(lower-case(@name),'ear')] or //*[star...

XML <Galaxy> <name>Milky Way</name> <CelestialObject name="Earth" type="planet"/> <CelestialObject name="Sun" type="star"/> </Galaxy> XPATH /Galaxy/*[ends-with(lower-case(@type),'tar')] or //*[ends-w...

This example uses Parallel.ForEach to calculate the sum of the numbers between 1 and 10000 by using multiple threads. To achieve thread-safety, Interlocked.Add is used to sum the numbers. using System.Threading; int Foo() { int total = 0; var numbers = Enumerable.Range(1, 10000).ToLis...

To switch the value of two variables you can use tuple unpacking. x = True y = False x, y = y, x x # False y # True

Schema Statics are methods that can be invoked directly by a Model (unlike Schema Methods, which need to be invoked by an instance of a Mongoose document). You assign a Static to a schema by adding the function to the schema's statics object. One example use case is for constructing custom queries:...