Tutorial by Examples: p

const url = 'http://api.stackexchange.com/2.2/questions?site=stackoverflow&tagged=javascript'; const questionList = document.createElement('ul'); document.body.appendChild(questionList); const responseData = fetch(url).then(response => response.json()); responseData.then(({item...

#include <stdio.h> #define SIZE (10) int main() { size_t i = 0; int *p = NULL; int a[SIZE]; /* Setting up the values to be i*i */ for(i = 0; i < SIZE; ++i) { a[i] = i * i; } /* Reading the values using pointers */ for(p =...

We use the null function to check if a given Map is empty: > Map.null $ Map.fromList [("Alex", 31), ("Bob", 22)] False > Map.null $ Map.empty True

The Data.Map module in the containers package provides a Map structure that has both strict and lazy implementations. When using Data.Map, one usually imports it qualified to avoid clashes with functions already defined in Prelude: import qualified Data.Map as Map So we'd then prepend Map funct...

C++11 A unary operator that determines whether the evaluation of its operand can propagate an exception. Note that the bodies of called functions are not examined, so noexcept can yield false negatives. The operand is not evaluated. #include <iostream> #include <stdexcept> void f...

The Repeat command, executed with the dot or period key (.), is more useful than it first appears. Once learned, you will find yourself using it often. Command:Description.Repeat the last change10.Repeat the last change 10 times So then, for a very simple example, if you make a change to line 1 by...

In Vim, these operations are handled differently from what you might be used to in almost any other modern editor or word processor (Ctrl-C, Ctrl-X, Ctrl-V). To understand, you need to know a little about registers and motions. Note: this section will not cover Visual Mode copying and cutting or ra...

C++11 A keyword denoting a null pointer constant. It can be converted to any pointer or pointer-to-member type, yielding a null pointer of the resulting type. Widget* p = new Widget(); delete p; p = nullptr; // set the pointer to null after deletion Note that nullptr is not itself a pointer. ...

sqlite> SELECT TYPEOF(NULL); null sqlite> SELECT TYPEOF(42); integer sqlite> SELECT TYPEOF(3.141592653589793); real sqlite> SELECT TYPEOF('Hello, world!'); text sqlite> SELECT TYPEOF(X'0123456789ABCDEF'); blob

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 ); > ...

You can define a method to accept an arbitrary number of keyword arguments using the double splat (**) operator: def say(**args) puts args end say foo: "1", bar: "2" # {:foo=>"1", :bar=>"2"} The arguments are captured in a Hash. You can manip...

By "class", we mean a type that was defined using the class or struct keyword (but not enum struct or enum class). Even an empty class still occupies at least one byte of storage; it will therefore consist purely of padding. This ensures that if p points to an object of an empty class...

SQLite has no separate data type for date or time values. ISO8601 strings The built-in keywords CURRENT_DATE, CURRENT_TIME, and CURRENT_TIMESTAMP return strings in ISO8601 format: > SELECT CURRENT_DATE, CURRENT_TIME, CURRENT_TIMESTAMP; CURRENT_DATE CURRENT_TIME CURRENT_TIMESTAMP --------...

This is very similar to using an Application subclass and overriding the attachBaseContext() method. However, using this method, you don't need to override attachBaseContext() as this is already done in the MultiDexApplication superclass. Extend MultiDexApplication instead of Application: package...

Automapper can be installed from nuget running the following command in Package Manager Console: Install-Package AutoMapper Then it can be included in different files within the project it has been installed to by using directives: using AutoMapper;

Unlike a parallel for-loop (parfor), which takes the iterations of a loop and distributes them among multiple threads, a single program, multiple data (spmd) statement takes a series of commands and distributes them to all the threads, so that each thread performs the command and stores the results....

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

You can use the archivesBaseName to set the name of apk. For example: defaultConfig { .... project.ext.set("archivesBaseName", "MyName-" + defaultConfig.versionName); } You will obtain this output. MyName-X.X.X-release.apk

To remove all elements from a Map, use the .clear() method: map.clear(); Example: const map = new Map([[1, 2], [3, 4]]); console.log(map.size); // 2 map.clear(); console.log(map.size); // 0 console.log(map.get(1)); // undefined

To remove an element from a map use the .delete() method. map.delete(key); Example: const map = new Map([[1, 2], [3, 4]]); console.log(map.get(3)); // 4 map.delete(3); console.log(map.get(3)); // undefined This method returns true if the element existed and has been removed, otherwise fal...