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You can convert a single function with a callback argument to a Promise-returning version with Promise.promisify, so this: const fs = require("fs"); fs.readFile("foo.txt", (err, data) => { if(err) throw err; console.log(data); }); becomes: const promisify = requ...

In order to convert any callback API to promises assuming the promisify and promisifyAll version doesn't fit - you can use the promise constructor. Creating promises generally means specifying when they settle - that means when they move to the fulfilled (completed) or rejected (errored) phase to i...

Ω-notation is used for asymptotic lower bound. Formal definition Let f(n) and g(n) be two functions defined on the set of the positive real numbers. We write f(n) = Ω(g(n)) if there are positive constants c and n0 such that: 0 ≤ c g(n) ≤ f(n) for all n ≥ n0. Notes f(n) = Ω(g(n)) means that f(n)...

Let f(n) and g(n) be two functions defined on the set of the positive real numbers, c, c1, c2, n0 are positive real constants. Notationf(n) = O(g(n))f(n) = Ω(g(n))f(n) = Θ(g(n))f(n) = o(g(n))f(n) = ω(g(n))Formal definition∃ c > 0, ∃ n0 > 0 : ∀ n ≥ n0, 0 ≤ f(n) ≤ c g(n)∃ c > 0, ∃ n0 > 0 ...

Expression trees represent code in a tree-like data structure, where each node is an expression Expression Trees enables dynamic modification of executable code, the execution of LINQ queries in various databases, and the creation of dynamic queries. You can compile and run code represented by expr...

A class or struct can have member functions as well as member variables. These functions have syntax mostly similar to standalone functions, and can be defined either inside or outside the class definition; if defined outside the class definition, the function's name is prefixed with the class' nam...

A common use of member functions is for encapsulation, using an accessor (commonly known as a getter) and a mutator (commonly known as a setter) instead of accessing fields directly. class Encapsulator { int encapsulated; public: int get_encapsulated() const { return encapsulated; }...

Member functions can also be declared virtual. In this case, if called on a pointer or reference to an instance, they will not be accessed directly; rather, they will look up the function in the virtual function table (a list of pointers-to-member-functions for virtual functions, more commonly know...

One of the primary uses for this cv-qualifiers is const correctness. This is the practice of guaranteeing that only accesses that need to modify an object are able to modify the object, and that any (member or non-member) function that doesn't need to modify an object doesn't have write access to t...

Starting a DSC on a remote machine is almost just as simple. Assuming you've already set up Powershell remoting (or enabled WSMAN). $remoteComputer = "myserver.somedomain.com" $cred = (Get-Credential) Start-DSCConfiguration -ServerName $remoteComputer -Credential $cred -Verbose Nb: A...

Detailed instructions on getting pthreads set up or installed.

Apart from primitives, the Explicit Layout structs (Unions) in C#, can also contain other Structs. As long as a field is a Value type and not a Reference, it can be contained in a Union: using System; using System.Runtime.InteropServices; // The struct needs to be annotated as "Explici...

To change the execution policy for the default scope (LocalMachine), use: Set-ExecutionPolicy AllSigned To change the policy for a specific scope, use: Set-ExecutionPolicy -Scope CurrentUser -ExecutionPolicy AllSigned You can suppress the prompts by adding the -Force switch.

Often you might need to execute an unsigned script that doesn't comply with the current execution policy. An easy way to do this is by bypassing the execution policy for that single process. Example: powershell.exe -ExecutionPolicy Bypass -File C:\MyUnsignedScript.ps1 Or you can use the shorthan...

Getting the effective execution policy for the current session: PS> Get-ExecutionPolicy RemoteSigned List all effective execution policies for the current session: PS> Get-ExecutionPolicy -List Scope ExecutionPolicy ----- --------------- MachinePolicy Undefined...

Sprite animation consists in showing an existing sequence of images or frames. First import a sequence of images to the asset folder. Either create some images from scratch or download some from the Asset Store. (This example uses this free asset.) Drag every individual image of a single animati...

In features/step_definitions/documentation.rb: When /^I go to the "([^"]+)" documentation$/ do |section| path_part = case section when "Documentation" "documentation" else raise "Unknown documentation section: #{section...

Local variables - Those declared within a procedure (subroutine or function) of a class (or other structure). In this example, exampleLocalVariable is a local variable declared within ExampleFunction(): Public Class ExampleClass1 Public Function ExampleFunction() As Integer Dim exa...

["Guten Tag " | [<<"Hello">>]]. [<<"Guten Tag ">> | [<<"Hello">>]]. [$G, $u, $t, $e, $n , $T, $a, $g | [<<"Hello">>]]. [71,117,116,101,110,84,97,103,<<"Hello">>].

<<"Guten tag, Hello">> = iolist_to_binary(["Guten tag, ",<<"Hello">>]). An IO list can be converted to a binary using the iolist_to_binary/1 function. If the data is going to be stored for a long period or sent as a message to other processes ...