Tutorial by Topics: on

There are many situations where it is useful to return several values from a function: for example, if you want to input an item and return the price and number in stock, this functionality could be useful. There are many ways to do this in C++, and most involve the STL. However, if you wish to avoi...

Use context processors to add variables that are accessible anywhere in your templates. Specify a function, or functions that return dicts of the variables you want, then add those functions to TEMPLATE_CONTEXT_PROCESSORS.

The built-in collections package provides several specialized, flexible collection types that are both high-performance and provide alternatives to the general collection types of dict, list, tuple and set. The module also defines abstract base classes describing different types of collection functi...

The $ character introduces parameter expansion, command substitution, or arithmetic expansion. The parameter name or symbol to be expanded may be enclosed in braces, which are optional but serve to protect the variable to be expanded from characters immediately following it which could be interprete...

RecyclerView addItemDecoration(RecyclerView.ItemDecoration decoration) RecyclerView addItemDecoration(RecyclerView.ItemDecoration decoration, int index) ParameterDetailsdecorationthe item decoration to add to the RecyclerViewindexthe index in the list of decorations for this RecyclerView. T...

See also separate topic on Overload Resolution Ambiguities can occur when one type can be implicitly converted into more than one type and there is no matching function for that specific type. For example: void foo(double, double); void foo(long, long); //Call foo with 2 ints foo(1, 2);...

UIButton : UIControl intercepts touch events and sends an action message to a target object when it's tapped. You can set the title, image, and other appearance properties of a button. In addition, you can specify a different appearance for each button state. Button Types A button’s type defi...

As more secure web services avoid storing passwords in plain text format, languages such as PHP provide various (undecryptable) hash functions to support the more secure industry standard. This topic provides documentation for proper hashing with PHP. string password_hash ( string $password , ...

This is a simple hello world function in Common Lisp. Examples will print the text Hello, World! (without quotation marks; followed by a newline) to the standard output. Common Lisp is a programming language that is largely used interactively using an interface known as a REPL. The REPL (Read Eva...

Due to the GIL (Global interpreter lock) only one instance of the python interpreter executes in a single process. So in general, using multi-threading only improves IO bound computations, not CPU-bound ones. The multiprocessing module is recommended if you wish to parallelise CPU-bound tasks. G...

While everything in Node.js is generally done asynchronously, require() is not one of those things. Since modules in practice only need to be loaded once, it is a blocking operation and should be used properly. Modules are cached after the first time they are loaded. Should you be editing a modul...

An assertion is a predicate that the presented condition must be true at the moment the assertion is encountered by the software. Most common are simple assertions, which are validated at execution time. However, static assertions are checked at compile time. assert(expression) static_assert(...

_Generic ( assignment-expression , generic-assoc-list ) ParameterDetailsgeneric-assoc-listgeneric-association OR generic-assoc-list , generic-associationgeneric-associationtype-name : assignment-expression OR default : assignment-expression All type qualifiers will be dropped during the ...

class twilio.rest.resources.Messages(*args, **kwargs) ParameterDetailsto (str)The destination phone number.from_ (str)The phone number sending this message (must be a verified Twilio number)body (str)The message you want to send, limited to 160 characters.status_callbackA URL that Twilio wil...

When using Channel Groups, you should not add or remove channels in your client side applications. This example shows adding channels to a channel group and subscribing to that channel group for simplicity sake. But in a real world scenario, you should have your server do all the add/remove of cha...

transition: <property> <duration> <timing-function> <delay>; @keyframes <identifier> [ [ from | to | <percentage> ] [, from | to | <percentage> ]* block ]* Transition ParameterDetailspropertyEither the CSS property to transition on, or all, which s...

One approach that can be taken to writing software is to create dependencies as they are needed. This is quite an intuitive way to write a program and is the way that most people will tend to be taught, partly because it is easy to follow. One of the issues with this approach is that it can be h...