Instruction: Compare and contrast the var, let, and const keywords in terms of scope, hoisting, and reassignment.
Context: This question is designed to assess the candidate's understanding of variable declarations, scopes, and block-level scoping in JavaScript.
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Scope: The var keyword declares a variable globally, or locally to an entire function regardless of block scope. This means if var is declared inside a block, like an if condition or a loop, it's accessible outside of that block, which can lead to unexpected behavior if not carefully managed. On the other hand, let and const introduce block-level scoping. This means a variable declared with either let or const inside a block (for example, within a loop or an if statement) is only accessible within that block. This block-level scope enhances code reliability and predictability since the variable cannot be accessed or modified from outside its intended scope.
Hoisting: Variables declared with var are hoisted, meaning they are raised...