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For every infix operator, e.g. + there is a operator-function (operator.add for +): 1 + 1 # Output: 2 from operator import add add(1, 1) # Output: 2 even though the main documentation states that for the arithmetic operators only numerical input is allowed it is possible: from operator impo...

Arbitrary number of positional arguments: Defining a function capable of taking an arbitrary number of arguments can be done by prefixing one of the arguments with a * def func(*args): # args will be a tuple containing all values that are passed in for i in args: print(i) fun...

class MyClass { func sayHi() { print("Hello") } deinit { print("Goodbye") } } When a closure captures a reference type (a class instance), it holds a strong reference by default: let closure: () -> Void do { let obj = MyClass() // Captures a strong re...

A for loop iterates over a sequence, so altering this sequence inside the loop could lead to unexpected results (especially when adding or removing elements): alist = [0, 1, 2] for index, value in enumerate(alist): alist.pop(index) print(alist) # Out: [1] Note: list.pop() is being used t...

There are several special variable types that a class can use for more easily sharing data. Instance variables, preceded by @. They are useful if you want to use the same variable in different methods. class Person def initialize(name, age) my_age = age # local variable, will be destroyed ...

We have three methods: attr_reader: used to allow reading the variable outside the class. attr_writer: used to allow modifying the variable outside the class. attr_accessor: combines both methods. class Cat attr_reader :age # you can read the age but you can never change it attr_writer...

Python 2.x2.3 raw_input will wait for the user to enter text and then return the result as a string. foo = raw_input("Put a message here that asks the user for input") In the above example foo will store whatever input the user provides. Python 3.x3.0 input will wait for the user ...

def input_number(msg, err_msg=None): while True: try: return float(raw_input(msg)) except ValueError: if err_msg is not None: print(err_msg) def input_number(msg, err_msg=None): while True: try: return ...

Python 2.x2.3 In Python 2.x, to continue a line with print, end the print statement with a comma. It will automatically add a space. print "Hello,", print "World!" # Hello, World! Python 3.x3.0 In Python 3.x, the print function has an optional end parameter that is what...

if (navigator.geolocation) { navigator.geolocation.getCurrentPosition(geolocationSuccess, geolocationFailure); } else { console.log("Geolocation is not supported by this browser."); } // Function that will be called if the query succeeds var geolocationSuccess = function(pos) {...

The following variables set up the below example: var COOKIE_NAME = "Example Cookie"; /* The cookie's name. */ var COOKIE_VALUE = "Hello, world!"; /* The cookie's value. */ var COOKIE_PATH = "/foo/bar"; /* The cookie's path. */ var COOKIE_EXPIRES; ...

This a Basic example for using the MVVM model in a windows desktop application, using WPF and C#. The example code implements a simple "user info" dialog. The View The XAML <Grid> <Grid.ColumnDefinitions> <ColumnDefinition Width="Auto"/> ...

git diff This will show the unstaged changes on the current branch from the commit before it. It will only show changes relative to the index, meaning it shows what you could add to the next commit, but haven't. To add (stage) these changes, you can use git add. If a file is staged, but was modi...

You can upvote (or downvote, if you want...) examples you created. Although you won't get any reputation for doing so, upvoting your the example will influence the examples' ordering on the page. Any previous contributors to the examples will get reputation. On the other hand, you might consider ...

Overview Checkboxes and radio buttons are written with the HTML tag <input>, and their behavior is defined in the HTML specification. The simplest checkbox or radio button is an <input> element with a type attribute of checkbox or radio, respectively: <input type="checkbox&quo...

Python's string type provides many functions that act on the capitalization of a string. These include : str.casefold str.upper str.lower str.capitalize str.title str.swapcase With unicode strings (the default in Python 3), these operations are not 1:1 mappings or reversible. Most of thes...

Python's str type also has a method for replacing occurences of one sub-string with another sub-string in a given string. For more demanding cases, one can use re.sub. str.replace(old, new[, count]): str.replace takes two arguments old and new containing the old sub-string which is to be replace...

git merge incomingBranch This merges the branch incomingBranch into the branch you are currently in. For example, if you are currently in master, then incomingBranch will be merged into master. Merging can create conflicts in some cases. If this happens, you will see the message Automatic merge ...

Functions in Swift may return values, throw errors, or both: func reticulateSplines() // no return value and no error func reticulateSplines() -> Int // always returns a value func reticulateSplines() throws // no return value, but may throw an error func reticulat...

Copying an array will copy all of the items inside the original array. Changing the new array will not change the original array. var originalArray = ["Swift", "is", "great!"] var newArray = originalArray newArray[2] = "awesome!" //originalArray = ["...