Weird JS

Description

This repository contains a collection of weird JavaScript behaviors that you might encounter while working with the language. Each problem is accompanied by an explanation and code examples to demonstrate the behavior.

Problems

Problem 1

Floating-point arithmetic precision issues:

console.log(0.1 + 0.2 === 0.3); // Output: false

When dealing with floating-point numbers in JavaScript, you may encounter precision issues due to the internal representation of numbers.

Problem 2

NaN comparison::

console.log(NaN === NaN); // Output: false

In JavaScript, NaN (Not a Number) is a special value used to represent the result of an operation that cannot produce a meaningful numeric result.

Problem 3

Type coercion:

console.log(1 + '1'); // Output: '11'

In JavaScript, type coercion refers to the automatic conversion of values from one data type to another. This can sometimes lead to unexpected behavior in expressions and operations.

Problem 3

Type coercion:

console.log(1 + '1'); // Output: '11'

In JavaScript, type coercion refers to the automatic conversion of values from one data type to another. This can sometimes lead to unexpected behavior in expressions and operations.

Problem 4

Implicit global variables:

function test() {
    a = 10;
}
test();
console.log(a); // Output: 10

In JavaScript, variables declared without the var, let, or const keyword inside a function become global variables, even if they are assigned values inside a function scope.

Problem 5

Truthy and falsy values:

console.log(Boolean('false')); // Output: true
console.log(Boolean('')); // Output: false

In JavaScript, certain values are considered falsy, such as an empty string, undefined, null, 0, NaN, and false. All other values are considered truthy.