Tutorial by Examples: en

The X-macro approach can be generalized a bit by making the name of the "X" macro an argument of the master macro. This has the advantages of helping to avoid macro name collisions and of allowing use of a general-purpose macro as the "X" macro. As always with X macros, the mas...

URLs for links can be specified later in the document. Markdown [Text1][1] will link to the first link, and [Text2][2] to the second. You [can reuse][1] names, and give longer names [like this one][a link]. You can also link text [like this] without giving the reference an explicit name. [1]:...

docker run docker/whalesay cowsay 'Hello, StackExchange!' This command tells Docker to create a container from the docker/whalesay image and run the command cowsay 'Hello, StackExchange!' in it. It should print a picture of a whale saying Hello, StackExchange! to your terminal. If the entrypoin...

An std::map takes (key, value) pairs as input. Consider the following example of std::map initialization: std::map < std::string, int > ranking { std::make_pair("stackoverflow", 2), std::make_pair("docs-beta", 1) }; In an std::...

Removing all elements: std::multimap< int , int > mmp{ {1, 2}, {3, 4}, {6, 5}, {8, 9}, {3, 4}, {6, 7} }; mmp.clear(); //empty multimap Removing element from somewhere with the help of iterator: std::multimap< int , int > mmp{ {1, 2}, {3, 4}, {6, 5}, {8, 9}, {3, 4}, {6, 7} }; ...

An element can be inserted into a std::map only if its key is not already present in the map. Given for example: std::map< std::string, size_t > fruits_count; A key-value pair is inserted into a std::map through the insert() member function. It requires a pair as an argument: fruits_c...

The container std::map has a member function empty(), which returns true or false, depending on whether the map is empty or not. The member function size() returns the number of element stored in a std::map container: std::map<std::string , int> rank {{"facebook.com", 1} ,{"goo...

You can create multiline code snippets by indenting each line with at least four spaces or one tab: #include <stdio.h> int main() { printf("Hello World!\n"); return 0; }

Some parsers allow code to be designated by adding three backticks before and after a section of code. ``` <p><em>This</em> is an HTML example!</p> ``` Optionally, many parsers allow adding syntax highlighting by specifying the code's language immediately after the firs...

Single-line comments in Lua start with -- and continue until the end of line: -- this is single line comment -- need another line -- huh? Block comments start with --[[ and end with ]]: --[[ This is block comment. So, it can go on... and on... and on.... ]] Block comme...

Constructors can be created with any kinds of arguments. public class TestClass { private String testData; public TestClass(String testData) { this.testData = testData; } } Called like this: TestClass testClass = new TestClass("Test Data"); A class can ...

main = do input <- getContents putStr input Input: This is an example sentence. And this one is, too! Output: This is an example sentence. And this one is, too! Note: This program will actually print parts of the output before all of the input has been fully read in. This m...

A bit counter-intuitive to the way most other languages' standard I/O libraries do it, Haskell's isEOF does not require you to perform a read operation before checking for an EOF condition; the runtime will do it for you. import System.IO( isEOF ) eofTest :: Int -> IO () eofTest line = do ...

Docker commands which take the name of a container accept three different forms: TypeExampleFull UUID9cc69f11a0f76073e87f25cb6eaf0e079fbfbd1bc47c063bcd25ed3722a8cc4aShort UUID9cc69f11a0f7Nameberserk_wozniak Use docker ps to view these values for the containers on your system. The UUID is generat...

Docker commands which take the name of an image accept four different forms: TypeExampleShort ID693bce725149Namehello-world (defaults to :latest tag)Name+taghello-world:latestDigesthello-world@sha256:e52be8ffeeb1f374f440893189cd32f44cb166650e7ab185fa7735b7dc48d619 Note: You can only refer to an im...

A ViewPager allows to show multiple fragments in an activity that can be navigated by either fliping left or right. A ViewPager needs to be feed of either Views or Fragments by using a PagerAdapter. There are however two more specific implementations that you will find most useful in case of using ...

Razor has its own comment syntax which begins with @* and ends with *@. Inline Comment: <h1>Comments can be @*hi!*@ inline</h1> Multi-line Comment: @* Comments can spread over multiple lines *@ HTML Comment You can also use the normal HTML comment syntax starting with &...

SQL TermsMongoDB TermsDatabaseDatabaseTableCollectionEntity / RowDocumentColumnKey / FieldTable JoinEmbedded DocumentsPrimary KeyPrimary Key (Default key _id provided by mongodb itself)

We use Notification.requestPermission to ask the user if he/she wants to receive notifications from our website. Notification.requestPermission(function() { if (Notification.permission === 'granted') { // user approved. // use of new Notification(...) syntax will now be succe...

After the user has approved a request for permission to send notifications, we can send a simple notification that says Hello to the user: new Notification('Hello', { body: 'Hello, world!', icon: 'url to an .ico image' }); This will send a notification like this: Hello Hello, world!