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json.Unmarshal from the package "encoding/json" decodes a JSON value into the value pointed by the given variable. The parameters are the value to decode in []bytes and a variable to use as a storage for the de-serialized value. The returned value is an error (on failure). encodedValue :...

With Git, you can (almost) always turn the clock back Don't be afraid to experiment with commands that rewrite history*. Git doesn't delete your commits for 90 days by default, and during that time you can easily recover them from the reflog: $ git reset @~3 # go back 3 commits $ git reflog c4...

The charset attribute specifies the character encoding for the HTML document and needs to be a valid character encoding (examples include windows-1252, ISO-8859-2, Shift_JIS, and UTF-8). UTF-8 (Unicode) is the most widely used and should be used for any new project. 5 <meta charset="UTF-8...

git diff 1234abc..6789def # old new E.g.: Show the changes made in the last 3 commits: git diff @~3..@ # HEAD -3 HEAD Note: the two dots (..) is optional, but adds clarity. This will show the textual difference between the commits, regardless of where they are in the tree.

This error appears while trying to update or delete records without including the WHERE clause that uses the KEY column. To execute the delete or update anyway - type: SET SQL_SAFE_UPDATES = 0; To enable the safe mode again - type: SET SQL_SAFE_UPDATES = 1;

A very useful feature of Swift 2.2 is having the ability of extending protocols. It works pretty much like abstract classes when regarding a functionality you want to be available in all the classes that implements some protocol (without having to inherit from a base common class). protocol FooPro...

Improper use of pointers are frequently a source of bugs that can include security bugs or program crashes, most often due to segmentation faults. Not checking for allocation failures Memory allocation is not guaranteed to succeed, and may instead return a NULL pointer. Using the returned value, w...

__construct() is the most common magic method in PHP, because it is used to set up a class when it is initialized. The opposite of the __construct() method is the __destruct() method. This method is called when there are no more references to an object that you created or when you force its deletion...

When contributors add to a project from different machines or operating systems, it may happen that they use different email addresses or names for this, which will fragment contributor lists and statistics. Running git shortlog -sn to get a list of contributors and the number of commits by them co...

Generally speaking, empty commits (or commits with state that is identical to the parent) is an error. However, when testing build hooks, CI systems, and other systems that trigger off a commit, it's handy to be able to easily create commits without having to edit/touch a dummy file. The --allow-e...

An extension that allows you to use Unicode characters in lieu of certain built-in operators and names. ASCIIUnicodeUse(s)::∷has type->→function types, lambdas, case branches, etc.=>⇒class constraintsforall∀explicit polymorphism<-←do notation*★the type (or kind) of types (e.g., Int :: ★)&g...

In C++, sequences of characters are represented by specializing the std::basic_string class with a native character type. The two major collections defined by the standard library are std::string and std::wstring: std::string is built with elements of type char std::wstring is built with e...

Lists in Elixir are linked lists. This means that each item in a list consists of a value, followed by a pointer to the next item in the list. This is implemented in Elixir using cons cells. Cons cells are simple data structures with a "left" and a "right" value, or a "he...

iex(1)> recompile Compiling 1 file (.ex) :ok

iex(1)> 1 + 1 2 iex(2)> v 2 iex(3)> 1 + v 3 See also: Get the value of a row with `v`

// View to hold the CAGradientLayer. let view: UIView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 320)) // Initialize gradient layer. let gradientLayer: CAGradientLayer = CAGradientLayer() // Set frame of gradient layer. gradientLayer.frame = view.bounds // Color a...

// View to hold the CAGradientLayer. let view: UIView = UIView(frame: CGRect(x: 0, y: 0, width: 320, height: 320)) // Initialize gradient layer. let gradientLayer: CAGradientLayer = CAGradientLayer() // Set frame of gradient layer. gradientLayer.frame = view.bounds // Color at the top of...

Initialize the UITapGestureRecognizer with a target, self in this case, and an action which is a method that has a single parameter: a UITapGestureRecognizer. After initialization, add it to the view that it should recognize taps in. Swift override func viewDidLoad() { super.viewDidLoad() ...

There are a number of collection types in Python. While types such as int and str hold a single value, collection types hold multiple values. Lists The list type is probably the most commonly used collection type in Python. Despite its name, a list is more like an array in other languages, mostl...

For instance, a computation involving commands to read and write from the prompt: First we describe the "commands" of our computation as a Functor data type {-# LANGUAGE DeriveFunctor #-} data TeletypeF next = PrintLine String next | ReadLine (String -> next) derivin...