Using Interfaces to Describe Types in TypeScript

Great clean voice! Great Tutorial anyway! I WANT MORE!

Thanks Oktay! Glad you enjoyed the video. This totally made my day.

I seem to be getting: Error:(..., ...) TS2683:'this' implicitly has type 'any' because it does not have a type annotation.. :/

Interesting, so if I do:

let attackFunc = function(this: any, opponent: any, attackWith: any) {

it works! But if I try to do it in ES syntax:

let attackFunc = (this: any, opponent: any, attackWith: any) => {

it doesn't, still throws the same error. :/

I think you figured it out, but if you're still wondering this isn't allowed as an arrow function argument. Here's a reference to the issue on Github.

Interesting, so if I do:

let attackFunc = function(this: any, opponent: any, attackWith: any) {

it works! But if I try to do it in ES syntax:

let attackFunc = (this: any, opponent: any, attackWith: any) => {

it doesn't, still throws the same error. :/

that's because arrow functions doesn't bind their own "this"

I could add better typing to the attack function by making these changes:

interface AttackFunction {
  (opponent: ComicBookCharacter, attackWith: number): number;
}

and then

function attack(
  this: ComicBookCharacter,
  opponent: ComicBookCharacter,
  attackWith: number
): number {
  opponent.health -= attackWith;
  console.log(
    `${this.alias} has just attacked ${opponent.alias}, who's health = ${
      opponent.health
    } `
  );
  return opponent.health;
}

this, I love.

Ah.Mazing. A little fast but that just means i get to watch it over and over :) Thank you!

Ari, this course is just amazing, Thank you so much!

inebriationLevel

After seeing it a second time, it all became clear, probably THE most important chapter of the course up till now - woaw🔥