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The wildly popular game gives players a place to socialize with others or simply escape while on lockdown for coronavirus

As shelter in place orders around the world have left many people trapped at home indefinitely, some have found a new place to meet up: inside the digital world of wildly popular Nintendo game Animal Crossing.

Released in late March, Animal Crossing: New Horizons quickly became the top game in the US. In it, users explore a carefree pastel environment, growing fruits and flowers, catching bugs or fish to sell, and making friends with other characters in an open-ended simulation.

Detailed pictures of planet glowing through clouds were taken with telescope in Hawaii

Astronomers have captured some of the highest resolution images of Jupiter ever obtained from the ground using a technique known as “lucky imaging”.

The observations, from the Gemini North telescope on Hawaii’s dormant volcano Mauna Kea, reveal lightning strikes and storm systems forming around deep clouds of water ice and liquid. The images show the warm, deep layers of the planet’s atmosphere glowing through gaps in thick cloud cover in a “jack-o-lantern”-like effect.

Teenagers affirm evidence that suggests they are particularly struggling with coronavirus crisis

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• See all our coronavirus coverage

When, in late February, Betsy Sheil turned 16, she thought she was staring down the end of secondary school, not the beginning of global pandemic.

“I was going to finish year 11 and do my GCSEs, then I was going to have a really long summer with my friends, hopefully go abroad – have that summer that everyone has.”

The brain works really hard to make sense of the constant stream of information coming at it, and for the most part it does a pretty good job. That said, a small shift in perspective can turn unassuming situations into double-take inducing photos of intriguing perspective. Your brain is doing its best, but at times it's name match against double-take causing images of skewed perspective.

As long as the choosing beggars continue to present themselves, it's up to the rest of the world to serve them up reality checks, free of charge. This particular impatient choosing beggar experienced a nice wakeup moment, after pestering an artist to rush a free drawing, after they already received one free drawing. The artist absolutely delivered. 

Just the idea of finding a worm in a salad is enough to send some shivers running up the spine. Fortunately, in this case, after the worm was discovered, a surprising, but welcomed customer service story developed. Basically, Sainsbury's pulled through in the clutch to address the situation with some serious grace. 

via http://anambitiousprojectcollapsing.blogspot.com/

The leading hypothesis for how the moon formed involves a collision between a Mars-sized object and Earth that would have boiled away elements like carbon, making its discovery on the moon a mystery

A pulmonary blood clot killed the brother of an Idaho woman who’s facing charges in the disappearance of her children — a case that attracted worldwide attention with revelations of her doomsday beliefs and connection to three mysterious deaths. Autopsy and toxicology reports were released Friday for Alex Cox, who died in Arizona in December. In July, Cox fatally shot his sister’s estranged husband, Charles Vallow, in what he said was self-defense.

The moves could include a gradual reopening of schools and allowing people to spend more time outside.

Ann Clwyd argues against "blanket ban" on over-70s involvement in easing of virus restrictions.

Joe Allington was persuaded to dance on TikTok for the first time in January. Now he's got 1.5 million followers.

The CEO of Methodist Homes says a secure supply chain from government would mean avoiding inflated prices.

The singer, who had Jamaica's first million-selling single, dies after suffering a stroke.

One of the most common problems that I run into when using Redux is trying to figure out why an action is not being captured by a reducer. For someone just getting starting with Redux, debugging this issue can be especially overwhelming because of how Redux manages data flow. So before you start pouring over configuration code, or the logic contained in your action creators and reducers, please, make sure your action types are defined and spelled correctly.

One of the most common problems that I run into when using Redux is trying to figure out why an action is not being captured by a reducer. For someone just getting starting with Redux, debugging this issue can be especially overwhelming because of how Redux manages data flow. So before you start pouring over configuration code, or the logic contained in your action creators and reducers, please, make sure your action types are defined and spelled correctly.

In any application that I have built, most bugs that I have run into are simply due to typos. However, the solution to this particular problem is harder to spot because no errors are raised when the application is run. Take a look at the snippet below.

// actionTypes.js

export const FETCH_FILE_REQUEST = 'fetch_file_request';
export const FETCH_FILE_SUCCESS = 'fetch_file_success';
export const FETCH_FILE_FAIL = 'fetch_file_fail';


// filesReducer.js

import {
  FETCH_FILE_REQUEST,
  FETCH_FILE_SUCESS,
  FETCH_FILE_FAIL
} from '../actions/actionTypes';

const filesReducer = (state = {}, action) => {
  switch (action.type) {
    case FETCH_FILE_SUCESS:
      return { ...state, file: action.payload };
    default:
      return state;
  }
}

export default filesReducer;

Assuming we dispatched an action with type FETCH_FILE_SUCCESS, the filesReducer should catch the action before the default case is returned. But what if that is not happening? Where do we start the debugging process. There does not appear to be anything wrong with the code in the reducer; the action type was imported and matches the case in the switch statement. There are no errors in the browser. Where is the issue?

You may have noticed that I misspelled SUCCESS in filesReducer.js, but the reason this can be hard to catch is because importing undefined types does not cause an error, so when we import FETCH_FILE_SUCESS, its value is actually undefined, so our reducer always hits the default case.

It would be nice if the existing import/export system could help us catch this. Unfortunately, since action types are just strings, validating their existence is challenging. Luckily, we have another option.

Enter Proxies

Proxies are a feature of ES2015 that allow us to customize operations on a object. They can be used in many different ways, and you can find some useful examples here and here. For our problem, this example from Mozilla looks promising:

let validator = {
  set: function(obj, prop, value) {
    if (prop === 'age') {
      if (!Number.isInteger(value)) {
        throw new TypeError('The age is not an integer');
      }
      if (value > 200) {
        throw new RangeError('The age seems invalid');
      }
    }

    // The default behavior to store the value
    obj[prop] = value;

    // Indicate success
    return true;
  }
};

let person = new Proxy({}, validator);

person.age = 100;
console.log(person.age); // 100
person.age = 'young'; // Throws an exception
person.age = 300; // Throws an exception

So if proxies can be used to validate that properties assigned to an object are of a certain type and value, we should definitely be able to ensure that our action types are never undefined, or else throw an error that will be easy for us to fix. Let’s refactor our actionTypes.js file.

// actionTypes.js

const types = {
  FETCH_FILE_REQUEST: 'fetch_file_request',
  FETCH_FILE_SUCCESS: 'fetch_file_success',
  FETCH_FILE_FAIL: 'fetch_file_fail'
}

const typeValidator = {
  get(obj, prop) {
    if (obj[prop]) {
      return prop;
    } else {
      throw new TypeError(`${prop} is not a valid action type`);
    }
  }
}

module.exports = new Proxy(types, typeValidator);

First, we define a object containing all our action types. Then we define our validator handler typeValidator. The get method inside our handler is called a trap, and provides access to the properties of a object. If the property we are looking for, an action type, in this case, exists in the types object, return that prop, unmodified. Otherwise, throw an error because the prop does not exist.

Finally, export a new proxy, passing the types object as the target and the typeValidator as the handler. However, it is important to note that the ES2015 module system does not work well with proxies, so module.exports and require() must be used for exporting and importing the types.

Barely any code needs to change in the reducer and action creator files, but in order for the action types to be imported successfully, we just need couple lines of code in a new file:

// actionTypesProxy.js

export const {
  FETCH_FILE_REQUEST,
  FETCH_FILE_SUCCESS,
  FETCH_FILE_FAIL,
} = require('./actionTypes');

// in the reducer and action creator files
// change '../actions/actionTypes' to
// '../actions/actionTypesProxy'

By creating a proxy to verify the existence of an action type, we no longer have to worry about correctly naming a property upon import because an error will be thrown in the browser console as soon as the application starts. So, reduce the number headaches you get when developing an application using Redux and start using proxies.

Interested in learning how to build applications using Redux with ReactJS. Check out this online course! Modern React with Redux