Arrow functions in JavaScript

-
Since their introduction arrow function have simplified how we declare functions in JavaScript arrow functions are similar to lambadas in kotlin programming language
Instead of writing a function as
function time (param){
    return Date.now()
}
You can simplify code by rewriting it as simply
let time (param) =>  {
    return Date.now()
}
Alternatively you can use a neatier syntax
let time = param => Date.now()
Arrow functions this context does not refer to their scope.

For further reading "learn es6 the dope way part ii arrow functions and the this keyword",

Comments

Post a Comment

Popular posts from this blog

How to wait for a promise within a loop block

-
JavaScript promises enable developers to write asynchronous applications in JavaScript Loops are ways of iterating elements For instance doing an asynchronous task within a for loop can be done as follows; Note that lag is used to emulate some delay. const items = [1, 2, 3, 4] const lag = async (delay) => {     return new Promise((resolve) =>         setTimeout(() => res(`${delay / 1000} sec`), delay)) } items.forEach(async (item) => {     const seconds = await lag(1000 * item)     console.log(seconds) }) expected output 1 sec 2 sec 3 sec 4 sec After running the code above every second some text was printed
Read more

JavaScript math methods

-
JavaScript comprehensive list of all JavaScript Math methods Math.round () {type} method {parameter} {Number} {description} It returns a given number rounded off to the nearest integer. ie Math.round(0.6251) // returns 1 or Math.round(1.7252) // returns 2 Math . pow () {type} method {parameter} {Number}, {Number} {description} It returns a given number raised to the power the exponent. ie Math.pow(2, 5) // returns 32 or Math.pow(7, 2) // returns 49 Math.sqrt () {type} method {parameter} {Number} {description} It returns the square root of a given integer. ie Math.sqrt(25) // returns 5 or Math.sqrt(64) // returns 8 Math.abs () {type} method {parameter} {Number} {description} It returns absolute positive value of a given number ie Math.abs(-10) // returns 10 or Math.abs(52) // returns 52 Math.ceil () {type} method {parameter} {Number} {description} It returns a smaller number which is greater or equal to the given integer. ie Math.ceil(9.87) // returns 10 or...
Read more

How to remove null elements from array in JavaScript

-
Every now and then arrays normally tend to have null or otherwise empty elements Array filter is a specialized JavaScript function for filtering array elements found to be matching a given criteria for example; const arr = ['max', 'duke'] In order to remove duke from elements of the array you can do it as follows; arr.filter(name => (name == 'duke' ? false : true)) // returns ['max'] You can filter empty and false elements as well, using a similar syntax as done above; const arr = ['max', null, 'duke'] arr.filter(name => name) // ['max', 'duke']
Read more

How to train a tfjs model on logic gates

-
Using tensorflow for JavaScript to train an artificial intelligence model to effectively evaluate and predict expected output of a logic gate given two inputs. training data is sourced from a two dimentional array truth table // logic truth table // ----------------- const truthTable = [     [         [[[0, 0], [0, 1], [1, 1], [1, 1]],         [[0], [1], [1], [1]]]     ] ]; The first pairs of numbers are the input proceeded by the output
Read more

How to iterate array elements using 'for loop' in JavaScript

-
JavaScript arrays are similar to arrays in c and in c like programming languages such as php among others In JavaScript arrays are simply collections of elements for instance Objects Numbers or other Arrays Declaring an array An array may be declared using the array constructor for instance const array = new Array() or as const array = [] Iterating an array using 'for' loop This is the implest and most common method to iterate an array is by using the 'for loop' am sure you're familiar with the syntax. take for Instance you want to iterate an array of integers and print each one of them. var ints = [1, 2, 3, 4] To iterate ints using for loop. for (var i = 0; i < ints.length; i++){         console.log(ints[i]) } // output will be // 1 // 2 // 3 // 4 In between the parentheses they are three procedures in three segments separated by colons first segment declares var i an index which gets incriminated in the third segment as long as...
Read more