Syntax example scan sheet for Javascript.

javascript_up_to_speed.js

// JavaScript up to speed

// variables
let integerVar = 10;
const stringVar = "Hello, JavaScript!";

// functions
function greet(name) {
  return "Hello " + name + "!";
}

// arrow function
const greetArrow = (name) => "Hello " + name + "!";

// for loop
for (let i = 0; i < 5; i++) {
  console.log("For loop iteration:", i);
}

// while loop
let count = 0;
while (count < 5) {
  console.log("While loop iteration:", count);
  count++;
}

// conditional if
if (integerVar > 5) {
  console.log("Integer is greater than 5");
} else if (integerVar === 5) {
  console.log("Integer is 5");
} else {
  console.log("Integer is less than 5");
}

// switch case
switch (true) {
  case integerVar > 5:
    console.log("Integer is greater than 5");
    break;
  case integerVar === 5:
    console.log("Integer is 5");
    break;
  default:
    console.log("Integer is less than 5");
}

// data structures
let myArray = [1, 2, 3, 4, 5];
let myObject = { a: 1, b: 2 };

// array methods
let doubled = myArray.map((x) => x * 2);
let filtered = myArray.filter((x) => x > 3);
let sum = myArray.reduce((acc, x) => acc + x, 0);

// exception handling
try {
  let result = 10 / 0;
  if (!isFinite(result)) {
    throw new Error("Math error: Division by zero");
  }
} catch (error) {
  console.error("Caught an error:", error.message);
}

// asynchronous programming
async function fetchData() {
  try {
    let response = await fetch("https://api.example.com");
    let data = await response.json();
    console.log("Data fetched:", data);
  } catch (error) {
    console.error("Error fetching data:", error);
  }
}

// DOM manipulation
document.getElementById("myButton").addEventListener("click", function () {
  alert("Button clicked!");
});