Tutorial by Examples: c

git rev-list --oneline master ^origin/master Git rev-list will list commits in one branch that are not in another branch. It is a great tool when you're trying to figure out if code has been merged into a branch or not. Using the --oneline option will display the title of each commit. The ^ ...

Functions can be declared without parameters or a return value. The only required information is a name (hello in this case). func hello() { print("Hello World") } Call a function with no parameters by writing its name followed by an empty pair of parenthesis. hello() //output...

Functions can take parameters so that their functionality can be modified. Parameters are given as a comma separated list with their types and names defined. func magicNumber(number1: Int) { print("\(number1) Is the magic number") } Note: The \(number1) syntax is basic String I...

In iOS 8 Apple introduced the self sizing cell. Layout your UITableViewCells with Autolayout explicitly and UITableView takes care of the rest for you. Row height is calculated automatically, by default rowHeight value is UITableViewAutomaticDimension. UITableView property estimatedRowHeight is use...

We can make an AJAX request to Stack Exchange's API to retrieve a list of the top JavaScript questions for the month, then present them as a list of links. If the request fails or the returns an API error, our promise error handling displays the error instead. 6 View live results on HyperWeb. c...

A data.frame is a special kind of list: it is rectangular. Each element (column) of the list has same length, and where each row has a "row name". Each column has its own class, but the class of one column can be different from the class of another column (unlike a matrix, where all elemen...

In order to begin building with PayPal APIs, you have to create an application to obtain a client ID and secret. Go to https://developer.paypal.com/developer/applications/, sign in, and click on "Create App", as shown below: Next, enter an application name, select the sandbox testing a...

When testing you PayPal integration on sandbox, you'll need to have sandbox user accounts set up to use to go through the payment flow. Go to https://developer.paypal.com/developer/accounts/, log in using your PayPal account, and click on "Create Account", as below: Enter in the accoun...

The GlobalFetch interface exposes the fetch function, which can be used to request resources. fetch('/path/to/resource.json') .then(response => { if (!response.ok()) { throw new Error("Request failed!"); } return response.json(...

cat file.txt will print the contents of a file. If the file contains non-ASCII characters, you can display those characters symbolically with cat -v. This can be quite useful for situations where control characters would otherwise be invisible. cat -v unicode.txt Very often, for interactive ...

man <command> This will show the manual page for the specified command. For example, man ping will show: PING(8) BSD System Manager's Manual PING(8) NAME ping -- send ICMP ECHO_REQUEST packets to network hosts SYNOPSIS ping [-AaCDdfno...

$url = "https://api.dropboxapi.com/2/users/get_current_account" $req = [System.Net.HttpWebRequest]::Create($url) $req.headers["Authorization"] = "Bearer <ACCESS_TOKEN>" $req.Method = "POST" $res = $req.GetResponse() Write-Host "Response Sta...

Static method can be inherited similar to normal methods, however unlike normal methods it is impossible to create "abstract" methods in order to force static method overriding. Writing a method with the same signature as a static method in a super class appears to be a form of overriding,...

Consider the below list comprehension: >>> def f(x): ... import time ... time.sleep(.1) # Simulate expensive function ... return x**2 >>> [f(x) for x in range(1000) if f(x) > 10] [16, 25, 36, ...] This results in two calls to f(x) for 1,000 values of...

This code creates a sticky footer. When the content doesn't reach the end of the viewport, the footer sticks to the bottom of the viewport. When the content extends past the bottom of the viewport, the footer is also pushed out of the viewport. View Result HTML: <div class="header"&gt...

To create a new Date object use the Date() constructor: with no arguments Date() creates a Date instance containing the current time (up to milliseconds) and date. with one integer argument Date(m) creates a Date instance containing the time and date corresponding to the Epoch time (...

Defining a new protocol: @protocol NewProtocol - (void)protocolMethod:(id)argument; - (id)anotherMethod; @end

Cascading and specificity are used together to determine the final value of a CSS styling property. They also define the mechanisms for resolving conflicts in CSS rule sets. CSS Loading order Styles are read from the following sources, in this order: User Agent stylesheet (The styles supplied b...

The !important declaration is used to override the usual specificity in a style sheet by giving a higher priority to a rule. Its usage is: property : value !important; #mydiv { font-weight: bold !important; /* This property won't be overridden by the ...

Data Manipulation Language (DML for short) includes operations such as INSERT, UPDATE and DELETE: -- Create a table HelloWorld CREATE TABLE HelloWorld ( Id INT IDENTITY, Description VARCHAR(1000) ) -- DML Operation INSERT, inserting a row into the table INSERT INTO HelloWorld (D...