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{
  "env": {
    "browser": true,
    "node": true,
    "es6": true
  },

  "plugins": ["react"],

  "ecmaFeatures": {

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-- 
-- There is a `t` table with 3 fields:
--   `uid` - user ID
--   `dt` - date and time of message
--   `s` - text of the message
--   Write an SQL query to retrieve date and text of the last message for all users.
  
-- schema
CREATE TABLE `user_message_log` (
  `id` int(11) NOT NULL AUTO_INCREMENT,

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/**

Find the minimum value in an array of strings using a loop. For example, for this array:
  a=['my','name','is','john','doe'];
  
**/

const sortByLengthOnly = arr => arr.sort( (a, b) => a.length - b.length)

const sortByLengthAndValue = arr => arr.sort( (a, b) => { 

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const factorial = n => n < 0 ? 'n must be > 0' : n < 2 ? 1 : n * factorial(n - 1)

for (let i = -2; i <= 10 ; i++ ) {
  console.time(`Time for ${i}`);
  console.log(`factorial(${i}) = ${factorial(i)}`)
  console.timeEnd(`Time for ${i}`)
}

console.log('-----')

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JavaScript Private Class Fields

taken from https://flaviocopes.com/javascript-private-class-fields/

Introduction and code samples on using private class fields in JavaScript.

Before the introduction of private class fields, we could not really enforce private properties on a class. We used conventions instead, maybe using _ as an hint that the field is private, like this:

class Counter {

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To remove a submodule you need to:

• Delete the relevant section from the .gitmodules file.
• Stage the .gitmodules changes git add .gitmodules
• Delete the relevant section from .git/config.
• Run git rm --cached path_to_submodule (no trailing slash).
• Run rm -rf .git/modules/path_to_submodule (no trailing slash).
• Commit git commit -m "Removed submodule "
• Delete the now untracked submodule files rm -rf path_to_submodule

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/**
 * Checks if dates are on the same day
 *
 * @param {Object} first First date to comapre
 * @param {Object} second Second date to compare
 */
const datesAreOnSameDay = (first, second) =>
  first.getFullYear() === second.getFullYear() &&
  first.getMonth() === second.getMonth() &&
  first.getDate() === second.getDate()

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// An example of recursive flattering of a given data (potentially multidimensional)

// 1.
// concat all the arrays of a given array and return a new array with a result
const concat = arr => [].concat(...arr)

// recursively flattern a given data into a new array (ES6)
const flattern = el => Array.isArray(el) ? concat(el.map(flattern)) : Array.of(el)

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How to make a page editable in the browser
There is a special and pretty secret mode in browsers, called design mode.


When you set a page into design mode, you can edit the content of the page directly inside the browser page, which is very handy to test some prototype or check out how a new headline would look, for example.

How do you enable it? Open the DevTools console, and type:

document.designMode = 'on'

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Read:
Most of them are based on streams, like csv-parser or node-csv.

Those are great to deal with CSV in a production system.

I like to keep things simple when I don’t have performance in mind. For example, for a one-time parsing of CSV that I had to do to consolidate my backend systems.

To do so, I used neat-csv, a package that exposes the csv-parser functionality to a simple async/await interface.

Install it using npm install neat-csv and require it in your app: