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Pull properties from an object passed into a function. This pattern simulates named parameters instead of relying on argument position. let user = { name: 'Jill', age: 33, profession: 'Pilot' } function greeting ({name, profession}) { console.log(`Hello, ${name} the ${pr...

PM> Install-Package EntityFramework -Version 6.1.2

The json_decode() function takes a JSON-encoded string as its first parameter and parses it into a PHP variable. Normally, json_decode() will return an object of \stdClass if the top level item in the JSON object is a dictionary or an indexed array if the JSON object is an array. It will also retur...

The json_encode function will convert a PHP array (or, since PHP 5.4, an object which implements the JsonSerializable interface) to a JSON-encoded string. It returns a JSON-encoded string on success or FALSE on failure. $array = [ 'name' => 'Jeff', 'age' => 20, 'active' => ...

In this case, building against API 23, so permissions are handled too. You must add in the Manifest the following permission (wherever the API level you're using): <uses-permission android:name="android.permission.CAMERA"/> We're about to create an activity (Camera2Activity.java...

This uses the Dropbox .NET SDK to download a file from the Dropbox API at the remote path /Homework/math/Prime_Numbers.txt to the local file Prime_Numbers.txt: using (var response = await client.Files.DownloadAsync("/Homework/math/Prime_Numbers.txt")) { using (var fileStream = File....

This uses the Dropbox Python SDK to create a shared link for a file and also supplies a requested visibility and expiration in the settings: import datetime import dropbox dbx = dropbox.Dropbox("<ACCESS_TOKEN>") expires = datetime.datetime.now() + datetime.timedelta(days=30...

int* foo(int bar) { int baz = 6; baz += bar; return &baz; /* (&baz) copied to new memory location outside of foo. */ } /* (1) The lifetime of baz and bar end here as they have automatic storage * duration (local variables), thus the returned pointer is not valid! */ ...

Let's say we have two classes, Cat and Dog. class Cat def eat die unless has_food? self.food_amount -= 1 self.hungry = false end def sound puts "Meow" end end class Dog def eat die unless has_food? self.food_amount -= 1 self.hungry = f...

Let's say you want to generate counts or subtotals for a given value in a column. Given this table, "Westerosians": NameGreatHouseAllegienceAryaStarkCerceiLannisterMyrcellaLannisterYaraGreyjoyCatelynStarkSansaStark Without GROUP BY, COUNT will simply return a total number of rows: SELE...

/* define a list of preprocessor tokens on which to call X */ #define X_123 X(1) X(2) X(3) /* define X to use */ #define X(val) printf("X(%d) made this print\n", val); X_123 #undef X /* good practice to undef X to facilitate reuse later on */ This example will result in the prep...

Due to auto unboxing, one can use a Boolean in an if statement: Boolean a = Boolean.TRUE; if (a) { // a gets converted to boolean System.out.println("It works!"); } That works for while, do while and the condition in the for statements as well. Note that, if the Boolean is null...

Basics The Reflection API allows one to check the class structure of the code at runtime and invoke code dynamically. This is very powerful, but it is also dangerous since the compiler is not able to statically determine whether dynamic invocations are valid. A simple example would be to get the p...

Syntax for accessing rows and columns: [, [[, and $ This topic covers the most common syntax to access specific rows and columns of a data frame. These are Like a matrix with single brackets data[rows, columns] Using row and column numbers Using column (and row) names Like a list: Wi...

var array = [3, 2, 1] Creating a new sorted array As Array conforms to SequenceType, we can generate a new array of the sorted elements using a built in sort method. 2.12.2 In Swift 2, this is done with the sort() method. let sorted = array.sort() // [1, 2, 3] 3.0 As of Swift 3, it has...

py.test is one of several third party testing libraries that are available for Python. It can be installed using pip with pip install pytest The Code to Test Say we are testing an addition function in projectroot/module/code.py: # projectroot/module/code.py def add(a, b): return a + b ...

A failing test will provide helpful output as to what went wrong: # projectroot/tests/test_code.py from module import code def test_add__failing(): assert code.add(10, 11) == 33 Results: $ py.test ================================================== test session starts ===============...

A typical email has three main components: A recipient (represented as an email address) A subject A message body Sending mail in PHP can be as simple as calling the built-in function mail(). mail() takes up to five parameters but the first three are all that is required to send an email (al...

Annotation types are defined with @interface. Parameters are defined similar to methods of a regular interface. @interface MyAnnotation { String param1(); boolean param2(); int[] param3(); // array parameter } Default values @interface MyAnnotation { String param1() defau...

The first argument of re.match() is the regular expression, the second is the string to match: import re pattern = r"123" string = "123zzb" re.match(pattern, string) # Out: <_sre.SRE_Match object; span=(0, 3), match='123'> match = re.match(pattern, string) ma...