Tutorial by Examples: t

# creates a function with no arguments, which returns 3 get_three = () -> return 3 # same as above get_three = -> 3 # creates a function with arguments add_three = (num) -> num + 3 # multiple arguments, etc. add = (a, b) -> a + b

// all variables `s` have the type `String` let s = "hi".to_string(); // Generic way to convert into `String`. This works // for all types that implement `Display`. let s = "hi".to_owned(); // Clearly states the intend of obtaining an owned obje...

We can define a function to perform function composition using anonymous function syntax: f ∘ g = x -> f(g(x)) Note that this definition is equivalent to each of the following definitions: ∘(f, g) = x -> f(g(x)) or function ∘(f, g) x -> f(g(x)) end recalling that in Julia,...

One application of closures is to partially apply a function; that is, provide some arguments now and create a function that takes the remaining arguments. Currying is a specific form of partial application. Let's start with the simple function curry(f, x) that will provide the first argument to a ...

A stream wrapper provides a handler for one or more specific schemes. The example below shows a simple stream wrapper that sends PATCH HTTP requests when the stream is closed. // register the FooWrapper class as a wrapper for foo:// URLs. stream_wrapper_register("foo", FooWrapper::class...

Detailed instructions on getting rcpp set up or installed.

This method works by incrementing an integer from 0 to the greatest index in the array. $colors = ['red', 'yellow', 'blue', 'green']; for ($i = 0; $i < count($colors); $i++) { echo 'I am the color ' . $colors[$i] . '<br>'; } This also allows iterating an array in reverse order wi...

Each array instance contains an internal pointer. By manipulating this pointer, different elements of an array can be retrieved from the same call at different times. Using each Each call to each() returns the key and value of the current array element, and increments the internal array pointer. ...

If there is no need for frontend in your next project, you can run sails new with additional flag --no-frontend. sails new NameOfProject --no-frontend This will generate everything needed for backend and will omit view, assets and grunt files. More about command line and sails-new: http://sails...

A chrome extension is seperated into a maximum of 4 parts: the background page the popup page one or more content scripts the options page Each part, since they are innately separate, require individual debugging. Keep in mind that these pages are separate, meaning that variables are not d...

Before talking about porting Firefox extensions from/to, one should know what WebExtensions is. WebExtensions - is a platform that represents an API for creating Firefox extensions. It uses the same architecture of extension as Chromium, as a result, this API is compatible in many ways with API in...

In the extension code you can use any chrome.* API if you decalared the required permissions. In addition, some API's works only from background pages, and some API's works only from content scripts. You can use most of chrome.tabs methods declaring any permissions. Now we focus on chrome.tabs.crea...

If you want to add nested routes you can write the following code in routes.rb file. resources :admins do resources :employees end This will generate following routes: admin_employees GET /admins/:admin_id/employees(.:format) employees#index POST ...

The following configuration options should be called on a Rails::Railtie object config.after_initialize: Takes a block which will be run after rails has initialized the application. config.asset_host: This sets the host for the assets. This is useful when using a Content Delivery Network. This i...

The following configuration options can be used for configuring assets config.assets.enabled: Determines whether the asset pipeline is enabled. This defaults to true config.assets.raise_runtime_errors: This enables runtime error checking. It's useful for development mode config.assets.compress:...

Rails allows you to configure what generators are used when running rails generate commands. This method, config.generators takes a block config.generators do |g| g.orm :active_record g.test_framework :test_unit end Here are some of the options OptionDescriptionDefaultassetsCreates asset...

Merge Sort is a divide-and-conquer algorithm. It divides the input list of length n in half successively until there are n lists of size 1. Then, pairs of lists are merged together with the smaller first element among the pair of lists being added in each step. Through successive merging and through...

Trees are a sub-type of the more general node-edge graph data structure. To be a tree, a graph must satisfy two requirements: It is acyclic. It contains no cycles (or "loops"). It is connected. For any given node in the graph, every node is reachable. All nodes are reachable throug...

After installing Julia, to launch the read-eval-print-loop (REPL): On Unix Systems Open a terminal window, then type julia at the prompt, then hit Return. You should see something like this come up: On Windows Find the Julia program in your start menu, and click it. The REPL should be launched...

The Julia REPL is an excellent calculator. We can start with some simple operations: julia> 1 + 1 2 julia> 8 * 8 64 julia> 9 ^ 2 81 The ans variable contains the result of the last calculation: julia> 4 + 9 13 julia> ans + 9 22 We can define our own variables usi...