Tutorial by Examples: b

When you make a subclass of a base class, you can construct the base class by using : base after the subclass constructor's parameters. class Instrument { string type; bool clean; public Instrument (string type, bool clean) { this.type = type; this.clean = c...

$.ajax({ url: 'https://api.dropboxapi.com/2/sharing/add_folder_member', type: 'POST', processData: false, data: JSON.stringify({"shared_folder_id": "84528192421","members": [{"member": {".tag": "email","email":...

# lambda using the arrow syntax hello_world = -> { 'Hello World!' } hello_world[] # 'Hello World!' # lambda using the arrow syntax accepting 1 argument hello_world = ->(name) { "Hello #{name}!" } hello_world['Sven'] # "Hello Sven!" the_thing = lambda do |magic, ...

An if statement checks whether a Bool condition is true: let num = 10 if num == 10 { // Code inside this block only executes if the condition was true. print("num is 10") } let condition = num == 10 // condition's type is Bool if condition { print("num is 10&...

Optionals must be unwrapped before they can be used in most expressions. if let is an optional binding, which succeeds if the optional value was not nil: let num: Int? = 10 // or: let num: Int? = nil if let unwrappedNum = num { // num has type Int?; unwrappedNum has type Int print(&quo...

from collections import Counter c = Counter(["a", "b", "c", "d", "a", "b", "a", "c", "d"]) c # Out: Counter({'a': 3, 'b': 2, 'c': 2, 'd': 2}) c["a"] # Out: 3 c[7] # not in the list (7 oc...

astring = 'thisisashorttext' astring.count('t') # Out: 4 This works even for substrings longer than one character: astring.count('th') # Out: 1 astring.count('is') # Out: 2 astring.count('text') # Out: 1 which would not be possible with collections.Counter which only counts single char...

(Note: All examples using let are also valid for const) var is available in all versions of JavaScript, while let and const are part of ECMAScript 6 and only available in some newer browsers. var is scoped to the containing function or the global space, depending when it is declared: var x = 4; /...

The and-operator (&&) and the or-operator (||) employ short-circuiting to prevent unnecessary work if the outcome of the operation does not change with the extra work. In x && y, y will not be evaluated if x evaluates to false, because the whole expression is guaranteed to be false....

Python 3.2+ has support for %z format when parsing a string into a datetime object. UTC offset in the form +HHMM or -HHMM (empty string if the object is naive). Python 3.x3.2 import datetime dt = datetime.datetime.strptime("2016-04-15T08:27:18-0500", "%Y-%m-%dT%H:%M:%S%z"...

Use Case CASE can be used in conjunction with SUM to return a count of only those items matching a pre-defined condition. (This is similar to COUNTIF in Excel.) The trick is to return binary results indicating matches, so the "1"s returned for matching entries can be summed for a count o...

in myapp/context_processors.py: from django.conf import settings def debug(request): return {'DEBUG': settings.DEBUG} in settings.py: TEMPLATES = [ { ... 'OPTIONS': { 'context_processors': [ ... 'myapp.context_processor...

project/jni/main.c #include <stdio.h> #include <unistd.h> int main(void) { printf("Hello world!\n"); return 0; } project/jni/Android.mk LOCAL_PATH := $(call my-dir) include $(CLEAR_VARS) LOCAL_MODULE := hello_world LOCAL_SRC_FILES := main.c include $(BU...

Given that the module from the Defining a Module section exists in the file test.js, you can import from that module and use its exported members: import {doSomething, MyClass, PI} from './test' doSomething() const mine = new MyClass() mine.test() console.log(PI) The somethingPrivate()...

Sometimes you may encounter members that have really long member names, such as thisIsWayTooLongOfAName(). In this case, you can import the member and give it a shorter name to use in your current module: import {thisIsWayTooLongOfAName as shortName} from 'module' shortName() You can import m...

To create a new branch, while staying on the current branch, use: git branch <name> Generally, the branch name must not contain spaces and is subject to other specifications listed here. To switch to an existing branch : git checkout <name> To create a new branch and switch to it...

$ git branch -d dev Deletes the branch named dev if its changes are merged with another branch and will not be lost. If the dev branch does contain changes that have not yet been merged that would be lost, git branch -d will fail: $ git branch -d dev error: The branch 'dev' is not fully merged...

<input type="submit" value="Submit"> A submit input creates a button which submits the form it is inside when clicked. You can also use the <button> element if you require a submit button that can be more easily styled or contain other elements: <button type=&...

The term "IFrame" means Inline Frame. It can be used to include another page in your page. This will yield a small frame which shows the exact contents of the base.html. <iframe src="base.html"></iframe>

The srcdoc attribute can be used (instead of the src attribute) to specify the exact contents of the iframe as a whole HTML document. This will yield an IFrame with the text "IFrames are cool!" <iframe srcdoc="<p>IFrames are cool!</p>"></iframe> If the...