Node.js · Theory

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Introduction

Amit only reaches for Introduction (getting started) when a hello server has to stay correct in localhost:3000.

Do Introduction (getting started) once by hand. node hello.js. Change one input. Say the new result out loud.

Without Introduction (getting started), localhost:3000 gets messy and a hello server is hard to trust.

Amit ships Introduction (getting started) in localhost:3000. That is the use case worth saying.

Introduction (getting started) miss — calling Node ‘a language’. Fix it before you talk about advanced Node.js.

Place Introduction (getting started) next to nearby Node.js work — node hello.js is the link.

Close Introduction (getting started) with: “If I skip it, a hello server goes wrong like this: calling Node ‘a language’.”

Diagram

  request
      │
      ▼
  event loop
      │ I/O done
      ▼
  response

Exam tip

Say Introduction (getting started) in one breath, then node hello.js, then calling Node ‘a language’.

Example

// Introduction
const users = [
  { id: 1, name: "Asha" },
  { id: 2, name: "Ravi" },
];

function findUser(id) {
  return users.find((u) => u.id === id) ?? null;
}

console.log(findUser(2));
console.log(users.map((u) => u.name));

Introduction: find user 2, then list names. Say both prints.

Short notes

DefIntroduction (getting started) — Amit uses it for a hello server in localhost:3000.
RuleIntroduction (getting started) → node hello.js.
RememberIntroduction (getting started) + npm (localhost:3000).
UseIntroduction (getting started) in localhost:3000 (a hello server).
TrapIntroduction (getting started) — calling Node ‘a language’.
ExIntroduction (getting started) → a hello server.

// Introduction const users = [ { id: 1, name: "Asha" }, { id: 2, name: "Ravi" }, ]; function findUser(id) { return users.find((u) => u.id === id) ?? null; } console.log(findUser(2)); console.log(users.map((u) => u.name));

Introduction

Example

Short notes

Questions

Introduction

Example

Short notes

Questions