Tutorial by Examples: ga

The pattern (p1, p2) is strict in the outermost tuple constructor, which can lead to unexpected strictness behaviour. For example, the following expression diverges (using Data.Function.fix): fix $ \(x, y) -> (1, 2) since the match on (x, y) is strict in the tuple constructor. However, the fo...

The following example code is slower than it needs to be : Map<String, String> map = new HashMap<>(); for (String key : map.keySet()) { String value = map.get(key); // Do something with key and value } That is because it requires a map lookup (the get() method) for each ...

Let's say you have a library that returns callbacks, for example the fs module in NodeJS: const fs = require("fs"); fs.readFile("/foo.txt", (err, data) => { if(err) throw err; console.log(data); }); We want to convert it to a promise returning API, with bluebird - ...

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...

On a 8 cores Linux machine using GCC version 4.4, the C codes can be compiled and run the following way: $ gcc -std=c99 -O3 -fopenmp loop.c -o loopc -lm $ OMP_NUM_THREADS=1 ./loopc Computing 1000000 cosines and summing them with 1 threads took 0.095832s $ OMP_NUM_THREADS=2 ./loopc Computing 100...

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)...

Signing a script is done by using the Set-AuthenticodeSignature-cmdlet and a code-signing certificate. #Get the first available personal code-signing certificate for the logged on user $cert = @(Get-ChildItem -Path Cert:\CurrentUser\My -CodeSigningCert)[0] #Sign script using certificate Se...

When signing personal scripts or when testing code signing it can be useful to create a self-signed code signing certificate. 5.0 Beginning with PowerShell 5.0 you can generate a self-signed code signing certificate by using the New-SelfSignedCertificate-cmdlet: New-SelfSignedCertificate -Friendl...

import XCTest @testable import PersonApp class PersonTests: XCTestCase { func test_completeName() { let person = Person(firstName: "Josh", lastName: "Brown") XCTAssertEqual(person.completeName(), "Josh Brown") } } Now let's discuss wh...

Unity networking provides the High Level API (HLA) to handle network communications abstracting from low level implementations. In this example we will see how to create a Server that can communicate with one or multiple clients. The HLA allows us to easily serialize a class and send objects of ...

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

The following example uses expect and receive to mock an Order's call to a CreditCardService, so that the test passes only if the call is made without having to actually make it. class Order def cancel CreditCardService.instance.refund transaction_id end end describe Order do des...

Utilizing .Net System.Security.Cryptography.HashAlgorithm namespace to generate the message hash code with the algorithms supported. $example="Nobody expects the Spanish Inquisition." #calculate $hash=[System.Security.Cryptography.HashAlgorithm]::Create("sha256").ComputeHas...

Some Java programmers have a general aversion to throwing or propagating exceptions. This leads to code like the following: public Reader getReader(String pathname) { try { return new BufferedReader(FileReader(pathname)); } catch (IOException ex) { System.out.println(&q...

Entity class @Entity @Table(name = "USER") public class User { @Id @Column(name = "ID") private Long id; @Column(name = "USERNAME") private String username; @ManyToOne @JoinColumn("ORGANIZATION_ID") pr...

get_defined_vars() returns an array with all the names and values of the variables defined in the scope in which the function is called. If you want to print data you can use standard functions for outputting human-readable data, like print_r or var_dump. var_dump(get_defined_vars()); Note: This...

Most Rails developers start by modifying their model information within the template itself: <h1><%= "#{ @user.first_name } #{ @user.last_name }" %></h1> <h3>joined: <%= @user.created_at.in_time_zone(current_user.timezone).strftime("%A, %d %b %Y %l:%M %p&q...

After accessing the Asset Store and viewing the asset you'd like to download, simply click the Download button. The button text may also be Buy Now if the asset has an associated cost. If you are viewing the Unity Asset Store through the web interface, the Download button text may instead display...

After the asset has been downloaded in Unity, the Download or Buy Now button will change to Import. Selecting this option will prompt the user with a Import Unity Package window, where the user may select the asset files of which they'd like to import within their project. Select Import to confirm...